Composition of organic compounds, optical film and method of production thereof

ABSTRACT

A composition includes at least one organic compound of a first type of the general formula I and at least one organic compound of a second type of the general structural formula II, wherein Core in formula I is a conjugated organic unit capable of forming a rigid rod-like macromolecule, Gk is a set of ionogenic side-groups providing solubility of the organic compound of the first type in a solvent and give rigidity to the rod-like macromolecule; and wherein Sys in formula II is an at least partially conjugated substantially planar polycyclic molecular system capable of forming board-like supramolecules via π-π-interaction, and X, Y, Z and Q are substituents. The composition is capable of forming a lyotropic liquid crystal solution, which can form a solid retardation layer of biaxial type substantially transparent to electromagnetic radiation in the visible spectral range. The type and degree of biaxiality of the said optical retardation layer is controlled by a molar ratio of the organic compounds of the first and the second type in the composition. An optical film comprising a solid retardation layer formed of the composition, a method of producing the optical film, and a vertical alignment liquid crystal display using said retardation layer are also provided.

FIELD OF THE INVENTION

The present invention relates generally to the field of organicchemistry and particularly to the optical retardation films with biaxialproperties for liquid crystal displays.

BACKGROUND OF THE INVENTION

The liquid crystal display (LCD) technology has made considerableprogress in the past years. There are a lot of TV sets, monitors andeven public displays based on LCD panels on the market. The market ofLCD is expected to keep growing in the near future.

The rapidly growing and changing market sets new tasks for researchersand manufacturers. Growing size of LCD diagonal, which has alreadyexceeded 100 inch size, imposes stronger restrictions onto the qualityof optical components. In case of retardation films, very small colorshift and ability to provide higher contrast ratio at wide viewingangles are required for high-quality viewing of large displays.

Nowadays there are still some disadvantages of LCD technology whichimpact the quality of liquid crystal displays and still make feasiblethe competitive technologies like plasma display panel (PDP) inlarge-size and cathode-ray tube (CRT) in mid-size displays. One ofdisadvantages is a decrease of contrast ratio at oblique viewing angles.In conventional LCD the viewing angle performance is strongly dependentupon polarizers' performance. Typical LCD comprises two dichroicpolarizers crossed at 90°. However, at oblique angles the angle betweenprojections of their axes deviates from 90°, and polarizers becomeuncrossed. The light leakage increases with increasing off-axis obliqueangle. This results in low contrast ratio at wide viewing angle alongthe bisector of crossed polarizers. Moreover, generally the lightleakage becomes worse because of the liquid crystal cell placed betweencrossed polarizers.

Off-axis contrast drop issue in LCD can be successfully solved usingphase retardation films, which represent optically anisotropicmaterials. In particular, biaxial retardation films which have threedifferent principal refractive indices can be used for opticalcompensation of LCD. In contrast with uniaxial retardation films, thebiaxial retardation films generally allow providing the bestcompensation effect using minimal number of compensating sheets.

Phase retardation optical films used for improvement of the LCD contrastat wide viewing angles are known in the art. Most of the conventionalphase retardation films are produced by stretching of polymers such aspolycarbonate, polyester, polynorbornene etc. Depending on the type ofthe stress employed on the polymeric film, it is possible to obtainuniaxial or biaxial retardation films of various types. However, theimprovement of its performance is difficult due to limitations of thestretching manufacturing process.

Besides the stretching of the amorphous polymeric films, other polymeralignment techniques are known in the art. Thermotropic liquidcrystalline polymers (LCP) can provide highly anisotropic filmscharacterized by various types of birefringence. The production of suchfilms comprises coating a polymer melt or solution on a substrate; forthe latter case the coating is followed by the solvent evaporation. Theadditional alignment actions are involved, such as an application of theelectric field, using of the alignment layer or coating onto a stretchedsubstrate. The after-treatment of the coating is at a temperature atwhich the polymer exhibits liquid crystalline phase and for a timesufficient for the polymer molecules to be oriented. Examples ofuniaxial and biaxial optical films production can be found in U.S. Pat.No. 5,132,147, and other patent documents and scientific publications.

Optical films can be also produced by coating of lyotropic liquidcrystalline (LLC) solutions based on low-molecular compounds capable offorming columnar supramolecules as also known as chromonics. Extensiveinvestigations aimed at developing new methods of fabricatingchromonic-based films through variation of the film depositionconditions have been described in U.S. Pat. No. 5,739,296 and otherpatent documents and scientific publications. Of particular interest isthe development of new compositions of lyotropic liquid crystalsutilizing modifying, stabilizing, surfactant and/or other additives inthe known compositions, which improve the characteristics of the films.The recent research has been directed to the materials used in themanufacturing of anisotropic films, polarizers and retarders for LCD andtelecommunications applications, such as (but not limited to) thosedescribed in P. Yeh, Optical Waves in Layered Media, New York, JohnWiley & Sons (1998), and P. Yeh, and C. Gu, Optics of Liquid CrystalDisplays, New York, John Wiley & Sons, (1999).

It has been shown that ultra-thin optically anisotropic birefringentfilms based on organic dye LLC systems can be produced using the knownmethods and technologies. In particular, manufacturing of thincrystalline optically anisotropic films based on disulfoacids ofdibenzimidazoles of naphthalenetetracarboxylic acid has been describedby P. Lazarev and M. Paukshto (in: Proceedings of 7th IDW, (2000), pp.1159-1160). In the above referenced films the molecules are packed withtheir minimal polarizability axis parallel to the film coatingdirection. This structure allows to produce uniaxial −A-plate or biaxialB_(A)-plate retardation film types.

Water soluble rigid-rod polymers are also known to exhibitself-assembled structures in aqueous solutions. Such polymers are usedas model objects which are able to reveal some mechanisms taking placein living organisms and implying natural rigid-rod polymers such asdeoxyribonucleic acid (DNA), proteins, polysaccharides, having greatabilities to form well-ordered structures by spontaneous self-assembly,which is fundamental to invoke their biological functions. As naturalrigid-rod polyelectrolytes are difficult to extract withoutdenaturation, synthetic analogues can be studied to investigate someaspects of polyelectrolites aggregation in aqueous solutions. Forexample, self-assembling properties of water-solublepoly(2,2′-disulfonylbenzidine terephtalamide (PBDT) were investigated byW. Yang et al. (Macromolecules, 41 (5), 1791-1799, 2008). The authorsinvestigated the PBDT sodium salt in different concentration regions. Itwas shown that at concentration exceeding 3 wt. % the PBDT molecules canform liquid crystalline state. The investigation of electrolyte effecthas also shown that adding of the salt (NaCl) enhances the associationprocesses in the PBDT solutions.

Shear-induced mesophase organization of synthetic polyelectrolytes inaqueous solution was described by T. Funaki et al. in Langmuir, 2004,val. 20, 6518-6520. Poly(2,2′-disulfonylbenzidine terephtalamide (PBDT)was prepared by an interfacial polycondensation reaction according tothe procedure known in the prior art. Using polarizing microscopy, theauthors observed lyotropic nematic phase in aqueous solutions in theconcentration range of 2.8-5.0 wt %. Wide angle X-ray diffraction studyindicated that in the nematic state the PBDT molecules show aninter-chain spacing, d, of 0.30-0.34 nm, which is constant regardless ofthe concentration (2.8-5.0 wt %). The d value is smaller than that ofthe ordinary nematic polymers (0.41-0.45 nm), suggesting that PBDT rodsin the nematic state have a strong inter-chain interaction in thenematic state to form the bundle-like structure despite theelectrostatic repulsion of sulfonate anions. In the concentration rangefrom 2 to 2.8 wt % a shear-induced birefringent (SIB) mesophase wasobserved.

A number of rigid rod water-soluble polymers were described by N. Sarkarand D. Kershner in Journal of Applied Polymer Science, Vol. 62, pp.393-408 (1996). The authors suggest these polymers for differentapplications such as enhanced oil recovery. For these applications, itis essential to have a water soluble shear stable polymer that canpossess high viscosity at very low concentration. It is known that rigidrod polymers can be of high viscosity at low molecular weight comparedwith the traditionally used flexible chain polymers such a hydrolyzedpoly-acrylamides. New sulfonated water soluble aromatic polyamides,polyureas, and polyimides were prepared via interfacial or solutionpolymerization of sulfonated aromatic diamines with aromaticdianhydrides, diacid chlorides, or phosgene. Some of these polymers hadsufficiently high molecular weight (<200,000 according to GPC data),extremely high intrinsic viscosity (˜65 dL/g), and appeared to transforminto a helical coil in salt solution. These polymers have been evaluatedin applications such as thickening of aqueous solutions, flocculationand dispersion stabilization of particulate materials, and membraneseparation utilizing cast films.

Synthesis and properties of solutions of water-soluble polyamides aredescribed by E. J. Vandenberg, W. R. Diveley, et al. in Journal ofPolymer Science: Part A: Polymer Chemistry, Vol. 27, pp. 3745-3757(1989). Poly[N,N′-(sulfo-phenylene)phthalamidles andpoly[N,N′-(sulfo-p-phenylene)pyromellitimidel were prepared inwater-soluble form and it was found that their solution demonstrateunique properties, in some respects similar to xanthan. The mostinvestigated polymer, poly[N,N′-(sulfo-p-phenylene)terephthalamide](PPT-S), was produced as the dimethylacetamide (DMAC) salt by thesolution polymerization of 2,5-diaminobenzenesulfonic acid withterephthaloyl chloride in DMAC containing LiCl. The isolated polymerrequires heating to be dissolved in water; the resulting solutions areviscous solutions or gels at concentrations as low as 0.4%. They arehighly birefringent, exhibit circular dichroism properties, and areviscosity-sensitive to the content of salt. Solutions of this polymermixed with those of guar or hydroxyethyl cellulose give significantlyenhanced viscosity. The polymer has a relatively low molecular weight,ca. 5000, as estimated from the viscosity data. Some meta- andpara-isomeric analogs of PPT-S were prepared; these polymers havesimilar properties except they are more soluble in water, and higherconcentrations are required to obtain significant viscosity.Poly[N,N′-(sulfo-p-phenylene) pyromellitimide] (PIM-S) was preparedsimilarly from 2,5-diaminobenzenesulfonic acid and pyromelliticdianhydride. Properties of its aqueous solutions are similar to those ofPPT-S. It appears that these relatively low-molecular-weight rigid-chainpolymers associate in water to form a network that results in viscoussolutions at low concentrations.

Self-assembling properties of sulfonated poly-paraphenyleneterephthalamides were considered as a function of number and relativeposition of sulfonic groups to the main chain by E. Mendes, S. Viale,and S. J. Picken in Proc. Symp. on Functional Polymer Materials, 2004.The authors report, that when the repeated unite contains only onesulfonic group, the structure of the aqueous solutions vary from gel incase of poly(sulfo-paraphenylene terephtalamide) to supramolecularnematic liquid crystal in the case of poly(paraphenylenesulfoterephthalamide). Thus the position of the sulfonic groupdramatically affects the structure of the solutions. When two sulfonicgroups are present in the repeating unit (in case ofpoly(sulfo-paraphenylene sulfoterephthalamide)), a molecularpolyelectrolyte lyotropic liquid crystal is formed.

The present invention provides solutions to the above referenceddisadvantages of the optical films for liquid crystal display or otherapplications, and discloses a new type of optical film, in particular abiaxial retardation layer.

SUMMARY OF THE INVENTION

The present invention provides a composition comprising at least oneorganic compound of a first type, and at least one organic compound of asecond type, wherein the organic compound of the first type has ageneral structural formula I

where Core is a conjugated organic unit capable of forming a rigidrod-like macromolecule, n is a number of the conjugated organic units inthe rigid rod-like macromolecule, Gk is a set of ionogenic side-groups,and k is a number of the side-groups in the set Gk; the ionogenicside-groups and the number k provide solubility of the organic compoundof the first type in the solvent and give rigidity to the rod-likemacromolecule; the number n provides molecule anisotropy that promotesself-assembling of the macromolecules in a solution of the organiccompound or its salt, andwherein the organic compound of the second type has a general structuralformula II

where Sys is an at least partially conjugated substantially planarpolycyclic molecular system; X, Y, Z and Q are substituents; substituentX is a carboxylic group —COOH, substituent Y is a sulfonic group —SO₃H,substituent Z is a carboxamide —CONH₂, substituent Q is a sulfonamide—SO₂NH₂, and m, h, p, v are 0, 1, 2, 3, or 4, the organic compound ofthe second type is capable of forming board-like supramolecules viaπ-π-interaction; the composition of the above described compounds ortheir salts is capable of forming a lyotropic liquid crystal solution;and the solution is capable of forming a solid retardation layersubstantially transparent to electromagnetic radiation in the visiblespectral range.

In a further aspect, the present invention provides an optical filmcomprising a substrate having front and rear surfaces, and at least onesolid retardation layer on the front surface of the substrate, whereinthe solid retardation layer comprises at least one organic compound ofthe first type and at least one organic compound of the second type,wherein the organic compound of the first type has a general structuralformula I

where Core is a conjugated organic unit capable of forming a rigidrod-like macromolecule, n is a number of the conjugated organic units inthe rigid rod-like macromolecule, Gk is a set of ionogenic side-groups,and k is a number of the side-groups in the set Gk; the ionogenicside-groups and the number k provide solubility of the organic compoundof the first type in the solvent and give rigidity to the rod-likemacromolecule; the number n provides molecule anisotropy that promotesself-assembling of the macromolecules in a solution of the organiccompound or its salt, andwherein the organic compound of the second type has a general structuralformula II

where Sys is an at least partially conjugated substantially planarpolycyclic molecular system; X, Y, Z and Q are substituents; substituentX is a carboxylic group —COOH, substituent Y is a sulfonic group —SO₃H,substituent Z is a carboxamide —CONH₂, substituent Q is a sulfonamide—SO₂NH₂, and m, h, p, v are 0, 1, 2, 3, or 4, wherein the organiccompound of the second type is capable of forming board-likesupramolecules via π-π-interaction. The solid optical retardation layeris substantially transparent to electromagnetic radiation in the visiblespectral range.

In yet further aspect, the present invention provides a method ofproducing an optical film, comprising the steps of

-   -   a) preparation of a lyotropic liquid crystal solution of a        composition comprising at least one organic compound of a first        type, and at least one organic compound of a second type,        wherein the organic compound of the first type has a general        structural formula I

where Core is a conjugated organic unit capable of forming a rigidrod-like macromolecule, n is a number of the conjugated organic units inthe rigid rod-like macromolecule, Gk is a set of ionogenic side-groups,and k is a number of the side-groups in the set Gk; the ionogenicside-groups and the number k provide solubility of the organic compoundof the first type in the solvent and give rigidity to the rod-likemacromolecule; and the number n provides molecule anisotropy thatpromotes self-assembling of the macromolecules in a solution of theorganic compound or its salt, andwherein the organic compound of the second type has a general structuralformula II

where Sys is an at least partially conjugated substantially planarpolycyclic molecular system; X, Y, Z and Q are substituents; substituentX is a carboxylic group —COOH, substituent Y is a sulfonic group —SO₃H,substituent Z is a carboxamide, substituent Q is a sulfonamide, and m,h, p, v are 0, 1, 2, 3, or 4, wherein the organic compound of the secondtype is capable of forming board-like supramolecules viaπ-π-interaction; and wherein the composition of the organic compounds ofthe first and the second type or their salts is capable to form alyotropic liquid crystal solution;

-   -   b) application of a liquid layer of the solution onto a        substrate, wherein the liquid layer is substantially transparent        to electromagnetic radiation in the visible spectral range;    -   c) application of an external alignment action onto said liquid        layer; and    -   d) drying to form a solid optical retardation layer.

In still further aspect, the present invention provides a liquid crystaldisplay comprising a vertical alignment mode liquid crystal cell, twopolarizers arranged on each side of the liquid crystal cell, and atleast one compensating structure located between said polarizers,wherein the polarizers have transmission axes which are perpendicular toeach other, and the compensating structure comprises at least oneretardation layer, wherein the retardation layer comprises at least oneorganic compound of the first type and at least one organic compound ofthe second type, wherein the organic compound of the first type has ageneral structural formula I

where Core is a conjugated organic unit capable of forming a rigidrod-like macromolecule, n is a number of the conjugated organic units inthe rigid rod-like macromolecule, Gk is a set of ionogenic side-groups,and k is a number of the side-groups in the set Gk; the ionogenicside-groups and the number k provide solubility of the organic compoundof the first type in the solvent and give rigidity to the rod-likemacromolecule; the number n provides molecule anisotropy that promotesself-assembling of the macromolecules in a solution of the organiccompound or its salt, andwherein the organic compound of the second type has a general structuralformula II

where Sys is an at least partially conjugated substantially planarpolycyclic molecular system; X, Y, Z and Q are substituents; substituentX is a carboxylic group —COOH, substituent Y is a sulfonic group —SO₃H,substituent Z is a carboxamide —CONH₂, substituent Q is a sulfonamide—SO₂NH₂, and m, h, p, v are 0, 1, 2, 3, or 4; wherein the organiccompound of the second type is capable of forming board-likesupramolecules via π-π-interaction; wherein the composition of theorganic compounds of the first and the second type or their salts iscapable of forming a lyotropic liquid crystal solution; and wherein thesolution is capable of forming a solid retardation layer of biaxial typesubstantially transparent to electromagnetic radiation in the visiblespectral range.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a polarizing microscopy image of the lyotropic liquidcrystal solution texture of poly(2,2′-disulfonyl-4,4′-benzidineterephthalamide) cesium salt (concentration is approximately 5.6 wt. %);

FIG. 2 shows the refractive index spectra of the organic retardationlayer prepared from poly(2,2′-disulfonyl-4,4′-benzidine terephthalamide)(6.0% solution) on a glass substrate;

FIG. 3 shows a polarizing microscopy image of the lyotropic liquidcrystal solution texture of4,4′-(5,5-dioxidodibenzol[b,d]thiene-3,7-diyl)dibenzensulfonic acidcesium salt (concentration is approximately 10 wt. %);

FIG. 4 shows the refractive index spectra of the organic retardationlayer prepared from4,4′-(5,5-dioxidodibenzol[b,d]thiene-3,7-diyl)dibenzensulfonic acidcesium salt (10% solution) on a glass substrate;

FIG. 5 shows a polarizing microscopy image of the lyotropic liquidcrystal solution texture of4,4′-(5,5-dioxidodibenzol[b,d]thiene-3,7-diyl)dibenzensulfonic acidlithium salt (concentration is approximately 15 wt. %);

FIG. 6 shows the refractive index spectra of the organic retardationlayer prepared from4,4′-(5,5-dioxidodibenzol[b,d]thiene-3,7-diyl)dibenzensulfonic acidlithium salt (15% solution) on a glass substrate;

FIG. 7 shows a polarizing microscopy image of the lyotropic liquidcrystal solution texture of composition ofpoly(2,2′-disulfonyl-4,4′-benzidine terephthalamide) and4,4′-(5,5-dioxidodibenzol[b,d]thiene-3,7-diyl)dibenzensulfonic acidcesium salts (total concentration is approximately 8 wt. %);

FIG. 8 shows a polarizing microscopy image of the optical filmcomprising solid optical retardation layer produced with Mayer rodcoating method and comprising a composition ofpoly(2,2′-disulfonyl-4,4′-benzidine terephthalamide) and4,4′-(5,5-dioxidodibenzol[b,d]thiene-3,7-diyl)dibenzensulfonic acidcesium salts;

FIG. 9 shows a polarizing microscopy image of the optical filmcomprising solid optical retardation layer produced with slot-diecoating method and comprising a composition ofpoly(2,2′-disulfonyl-4,4′-benzidine terephthalamide) and4,4′-(5,5-dioxidodibenzol[b,d]thiene-3,7-diyl)dibenzensulfonic acidcesium salts;

FIGS. 10-16 show the refractive index spectra of the organic retardationlayers prepared from the composition ofpoly(2,2′-disulfonyl-4,4′-benzidine terephthalamide) and4,4′-(5,5-dioxidodibenzol[b,d]thiene-3,7-diyl)dibenzensulfonic acidcesium salts (aqueous solutions) on a glass substrate;

FIGS. 17a-d illustrate the control of the retardation layer type;

FIG. 18 shows the achievable values of NZ-factor of retardation layervs. ratio of the first and second type components in a composition;

FIG. 19 schematically shows the cross section of an optical film formedon a substrate, further comprising adhesive and protective layers.

FIG. 20 schematically shows the cross section of an optical film with anadditional antireflective layer.

FIG. 21 schematically shows the cross section of an optical film with anadditional reflective layer.

FIG. 22 schematically shows the cross section of an optical film with adiffuse or specular reflector as a substrate.

FIG. 23 schematically shows the general scheme of VA LCD compensatedwith biaxial A_(C)-type plate retarder.

FIGS. 24a and 24b show the simulated viewing angle contrast ratio map atwavelength λ=550 nm of VA LCD compensated with biaxial A_(C)-type plateretarder.

FIGS. 25a and 25b show the simulated viewing angle contrast ratio map atwavelength λ=550 nm of the non-compensated multidomain verticalalignment liquid crystal display (MVA LCD).

FIG. 26 shows the optical layers of the simulated multidomain verticalalignment liquid crystal display (MVA LCD) compensated with a biaxialAC-type plate and uniaxial negative C-plate according to the presentinvention.

FIGS. 27a and 27b show the contrast ratio vs. viewing angle of optimaldouble-plate compensated MVA LCD.

FIG. 28 shows the contrast ratios vs. viewing angle for no compensation(curve 1), single plate compensation (curve 2), and double platecompensation (curve 3) of multidomain vertical alignment liquid crystaldisplay (MVA LCD).

DETAILED DESCRIPTION OF THE INVENTION

The general description of the present invention having been made, afurther understanding can be obtained by reference to the specificpreferred embodiments, which are given herein only for the purpose ofillustration and are not intended to limit the scope of the appendedclaims.

Definitions of various terms used in the description and claims of thepresent invention are listed below.

The term “visible spectral range” refers to a spectral range having thelower boundary approximately equal to 400 nm, and upper boundaryapproximately equal to 700 nm.

The term “retardation layer” refers to an optically anisotropic layerwhich is characterized by three principal refractive indices (n_(x),n_(y) and n_(z)), wherein two principal directions for refractiveindices n_(x) and n_(y) belong to xy-plane coinciding with a plane ofthe retardation layer and one principal direction for refractive index(n_(z)) coincides with a normal line to the retardation layer.

The term “optically anisotropic biaxial retardation layer” refers to anoptical layer which refractive indices n_(x), n_(y), and n_(z) obey thefollowing condition in the visible spectral range: n_(x)≠n_(z)≠n_(y).

The term “optically anisotropic retardation layer of A_(C)-type” refersto an optical layer which refractive indices n_(x), n_(y), and n_(z)obey the following condition in the visible spectral range:n_(z)<n_(y)<n_(x).

The term “optically anisotropic retardation layer of B_(A)-type” refersto an optical layer which refractive indices n_(x), n_(y), and n_(z)obey the following condition in the visible spectral range:n_(x)<n_(z)<n_(y).

The term “NZ-factor” refers to the quantitative measure of degree ofbiaxiality which is calculated as follows:

${NZ} = \frac{{{Max}( {n_{x},n_{y}} )} - n_{z}}{{{Max}( {n_{x},n_{y}} )} - {{Max}( {n_{x},n_{y}} )}}$The above mentioned definitions are invariant to rotation of system ofcoordinates (of the laboratory frame) around of the vertical z-axis forall types of anisotropic layers.

As used herein, a “front substrate surface” refers to a surface facing aviewer. A “rear substrate surface” refers to the surface opposite to thefront surface.

The term “board-like supramolecule” refers to a supramolecule, thelongitudinal (L) and cross-section sizes (width S and height H) of whichsatisfy to the following ratio: L>>S≧H.

In one preferable embodiment of the present invention, a composition isprovided comprising at least one organic compound of a first type, andat least one organic compound of a second type, wherein the organiccompound of the first type has a general structural formula I

where Core is a conjugated organic unit capable of forming a rigidrod-like macromolecule, n is a number of the conjugated organic units inthe rigid rod-like macromolecule, Gk is a set of ionogenic side-groups,and k is a number of the side-groups in the set Gk; the ionogenicside-groups and the number k provide solubility of the organic compoundof the first type in the solvent and give rigidity to the rod-likemacromolecule; the number n provides molecule anisotropy that promotesself-assembling of the macromolecules in a solution of the organiccompound or its salt, and wherein the organic compound of the secondtype has a general structural formula II

where Sys is an at least partially conjugated substantially planarpolycyclic molecular system; X, Y, Z and Q are substituents; substituentX is a carboxylic group —COOH, substituent Y is a sulfonic group —SO₃H,substituent Z is a carboxamide —CONH₂, substituent Q is a sulfonamide—SO₂NH₂ and m, h, p, v are 0, 1, 2, 3, or 4; the organic compound of thesecond type is capable of forming board-like supramolecules viaπ-π-interaction; the composition of the above described compounds ortheir salts is capable of forming a lyotropic liquid crystal solution;and the solution is capable of forming a solid retardation layer ofbiaxial type substantially transparent to electromagnetic radiation inthe visible spectral range.

In one embodiment of the disclosed composition, the type and degree ofbiaxiality of the solid retardation layer is controlled by a molar ratioof the organic compounds of the first and the second type in thecomposition. In another embodiment of the disclosed composition, thenumber k is equal to 0, 1, 2, 3, 4, 5, 6, 7, or 8, and the number n isan integer in the range from 10 to 10000. In yet another embodiment ofthe disclosed composition, the organic compound of the first type has apolymeric main rigid-chain, wherein the conjugated organic units are thesame. In still another embodiment of the disclosed composition, theorganic compound of the first type has a copolymeric main rigid-chain,wherein at least one conjugated organic unit is different from others.In one embodiment of the disclosed composition, the number k is morethan 1, and the ionogenic side-groups are the same. In anotherembodiment of the disclosed composition, the number k is more than 1,and at least one said ionogenic side-group is different from others. Instill another embodiment of the disclosed composition, at least oneconjugated organic unit (Core) of the organic compound of the first typehas a general structural formula III−(Core1)−S1−(Core2)−S2−  (III)wherein Core1 and Core2 are conjugated organic components, and spacersS1 and S2 are selected independently from the list comprising —C(O)—NH—,—NH—C(O)—, —O—NH—, linear and branched (C₁-C₄)alkylenes, linear andbranched (C₁-C₄)alkenylenes, —O—CH₂—, —CH₂—O—, —CH═CH—, —CH═CH—C(O)O—,—O(O)C—CH═CH—, —C(O)—CH₂—, —OC(O)—O—, —IC(O)—, —C≡C—, —C(O)—S—, —S—,—S—C(O)—, —O—, —NH—, —N(CH₃)—. In yet another embodiment of thedisclosed composition, at least one rigid-core polymer is copolymerhaving the general structural formula IV[−(Core1)−S1−(Core2)−S2−]_(n-t)[−(Core3)−S3−[(Core4)−S4−]_(j)]_(t)  (IV)wherein Core1, Core2, Core3 and Core4 are conjugated organic components,spacers S1, S2, S3 and S4 are selected independently from the listcomprising —C(O)—NH—, —NH—C(O)—, —O—NH—, linear and branched (C₁-C₄)alkylenes, linear and branched (C₁-C₄)alkenylenes, (C₂-C₂₀) polyethyleneglycols, —O—CH₂—, —CH₂—O—, —CH═CH—, —CH═CH—C(O)O—, —O(O)C—CH═CH—,—C(O)—CH₂—, —OC(O)—O—, —OC(O)—, —C≡C—, —C(O)—S—, —S—, —S—C(O)—, —O—,—NH—, —N(CH₃)—, n is an integer in the range from 10 to 10000, t is aninteger in the range from 1 to n−1 and j is 0 or 1, and wherein at listone conjugated organic component out of Core3 and Core4 differs fromCore1 and Core2.

Examples of the conjugated organic components Core1, Core2, Core3 andCore4 of the organic compound of the first type represented by thegeneral structural formulas (III) and (IV) are given in Table 1.

TABLE 1 Examples of the structural formulas of Core1, Core2, Core3 andCore4 according to the present invention.

(1)

(2)

The ionogenic side-groups G are the same or different and independentlyselected from the list comprising —COOH, —SO₃H, and —H₂PO₃, k is equalto 0, 1 or 2, and p is equal to 1, 2 or 3.

In still another embodiment the organic compound of the first type ofthe general structural formula (I) is selected from structures 3 to 13given in Table 2, wherein the ionogenic side-group G is sulfonic group—SO₃H, and k is equal to 1 or 2.

TABLE 2 Examples of the structural formulas of the organic compounds ofthe first type according to the present invention.

 (3) Poly(2,2′-disulfo-4,4′-benzidine terephthalamide)

 (4) Poly(2,2′-disulfo-4,4′-benzidine sulfoterephthalamide)

 (5) Poly(para-phenylene sulfoterephthalamide)

 (6) Poly(2-sulfo-1,4-phenylene sulfoterephthalamide)

 (7) Poly(2,2′-disulfo-4,4′-benzidine naphthalene-2,6-dicarboxamide)

 (8) Poly(disulfobiphenylene-1,2-ethylene-2,2′-disulfobiphenylene

 (9) Poly(2,2′-disulfobiphenyl-dioxyterephthaloyl)

(10) Poly(2,2′-disulfobiphenyl-2-sulfodioxyterephthaloyl)

(11) Poly(sulfophenylene-1,2-ethylene-2,2′-disulfophenylene)

(12) Poly(2-sulfophenylene-1,2-ethylene-2′-sulfophenylene)

(13) Poly(2,2′-disulfobiphenyl-2-sulfo-1,4-dioxymethylphenylene)

In still another embodiment of the disclosed composition, the organiccompound of the first type further comprises additional side-groupsindependently selected from the list comprising linear and branched(C₁-C₂₀)alkyl, (C₂-C₂₀)alkenyl, and (C₂-C₂₀)alkinyl

In yet another embodiment of the disclosed composition, at least one ofthe additional side-groups of the organic compound of the first type isconnected with the Core via a bridging group A selected from the listcomprising —C(O)—, —C(O)O—, —C(O)—NH—, —(SO₂)NH—, —O—, —CH₂O—,—NH—, >N—, and any combination thereof.

In one embodiment of the disclosed composition, the salt of the organiccompound of the first type is selected from the list comprising ammoniumand alkali-metal salts.

At least partially conjugated substantially planar polycyclic molecularsystems Sys of the organic compound of the second type is selected fromstructures 14 to 27 given in Table 3.

TABLE 3 Examples of at least partially conjugated substantially planarpolycyclic molecular systems Sys

(14)

(15)

(16)

(17)

(18)

(19)

(20)

(21)

(22)

(23)

(24)

(25)

(26)

(27)

In other embodiment the organic compounds of the second type of thegeneral structural formula (II) is selected from structures 28 to 35given in Table 4, where the molecular system Sys is selected fromstructures 14 and 21 to 27 of Table 3 and the substituent is a sulfonicgroup —SO₃H, and m, p, v, and w are equal to 0.

TABLE 4 Examples of the structural formulas of the organic compounds ofthe second type according to the present invention.

(28) 4,4′-(5,5-dioxidodibenzo[b,d]thiene-3,7-diyl)dibenzenesulfonicacid, where Sys has the general structural formula (14)

(29) dinaphto[2,3-b:2′,3′-d]furan disulfonic acid, where Sys has thegeneral structural formula (21)

(30) 12H-benzo[b]phenoxazine disulfonic acid, where Sys has the generalstructural formula (24)

(31) dibenzo[b,i]oxanthrene disulfonic acid, where Sys has the generalstructural formula (22)

(32) benzo[b]naphto[2′,3′:5,6]dioxino[2,3-i]oxanthrene disulfonic acid,where Sys has the general structural formula (23)

(33) acenaphtho[1,2-b]benzo[g]quinoxaline disulfonic acid, where Sys hasthe general structural formula (25)

(34) 9H-acenaphtho[1,2-b]imidazo[4,5-g]quinoxaline disulfonic acid,where Sys has the general structural formula (26)

(35) dibenzo[b,def]chrysene-7,14-dion disulfonic acid, where Sys has thegeneral structural formula (27)

In another embodiment the disclosed composition further comprisesinorganic compounds which are selected from the list comprisinghydroxides and salts of alkali metals.

In a further aspect, the present invention provides an optical filmcomprising a substrate having front and rear surfaces, and at least onesolid retardation layer on the front surface of the substrate, whereinthe solid retardation layer comprises at least one organic compound ofthe first type and at least one organic compound of the second type,wherein the organic compound of the first type has a general structuralformula I

where Core is a conjugated organic unit capable of forming a rigidrod-like macromolecule, n is a number of the conjugated organic units inthe rigid rod-like macromolecule, Gk is a set of ionogenic side-groups,and k is a number of the side-groups in the set Gk; the ionogenicside-groups and the number k provide solubility of the organic compoundof the first type in the solvent and give rigidity to the rod-likemacromolecule; the number n provides molecule anisotropy that promotesself-assembling of the macromolecules in a solution of the organiccompound or its salt, andwherein the organic compound of the second type has a general structuralformula II

where Sys is an at least partially conjugated substantially planarpolycyclic molecular system; X, Y, Z and Q are substituents; substituentX is a carboxylic group —COOH, substituent Y is a sulfonic group —SO₃H,substituent Z is a carboxamide —CONH₂, substituent Q is a sulfonamide—SO₂NH₂, and m, h, p, v are 0, 1, 2, 3, or 4; wherein the organiccompound of the second type is capable of forming board-likesupramolecules via π-π-interaction; wherein the composition of theorganic compounds of the first and the second type or their salts iscapable of forming a lyotropic liquid crystal solution; and wherein thesolution is capable of forming a solid retardation layer of biaxial typesubstantially transparent to electromagnetic radiation in the visiblespectral range.

In one embodiment of the disclosed optical film, the type and degree ofbiaxiality of the said optical retardation layer is controlled by amolar ratio of the organic compounds of the first and the second type inthe composition. In another embodiment of the disclosed optical film,the number k is equal to 0, 1, 2, 3, 4, 5, 6, 7, or 8, and the number nis an integer in the range from 10 to 10000. In yet another embodimentof the disclosed optical film, the organic compound of the first typehas a polymeric main rigid-chain, wherein the conjugated organic unitsare the same. In still another embodiment of the disclosed optical film,the organic compound of the first type has a copolymeric mainrigid-chain, wherein at least one conjugated organic unit is differentfrom others. In one embodiment of the disclosed optical film, the numberk is more than 1, and the ionogenic side-groups are the same. In anotherembodiment of the disclosed optical film, the number k is more than 1,and at least one said ionogenic side-group is different from others.

In still another embodiment of the disclosed optical film, at least oneconjugated organic unit (Core) of the organic compound of the first typehas a general structural formula III−(Core1)−S1−(Core2)−S2−  (III)wherein Core1 and Core2 are conjugated organic components, and spacersS1 and S2 are selected independently from the list comprising —C(O)—NH—,—NH—C(O)—, —O—NH—, linear and branched (C₁-C₄)alkylenes, linear andbranched (C₁-C₄)alkenylenes, —O—CH₂—, —CH₂—O—, —CH═CH—, —CH═CH—C(O)O—,—O(O)C—CH═CH—, —C(O)—CH₂—, —OC(O)—O—, —OC(O)—, —C≡C—, —C(O)—S—, —S—,—S—C(O)—, —O—, —NH—, —N(CH₃)—. In yet another embodiment of thedisclosed optical film, at least one rigid-core polymer is copolymerhaving the general structural formula IV[-(Core1)-S1-(Core2)-S2-]_(n-t)[-(Core3)-S3-[(Core4)-S4-]_(j)]_(t)  (IV)wherein Core1, Core2, Core3 and Core4 are conjugated organic components,spacers S1, S2, S3 and S4 are selected independently from the listcomprising —C(O)—NH—, —NH—C(O)—, —O—NH—, linear and branched (C₁-C₄)alkylenes, linear and branched (C₁-C₄)alkenylenes, (C₂-C₂₀) polyethyleneglycols, —O—CH₂—, —CH₂—O—, —CH═CH—, —CH═CH—C(O)O—, —O(O)C—CH═CH—,—C(O)—CH₂—, —OC(O)—O—, —OC(O)—, —C≡C—, —C(O)—S—, —S—, —S—C(O)—, —O—,—NH—, —N(CH₃)—, n is an integer in the range from 10 to 10000, t is aninteger in the range from 1 to n−1 and j is 0 or 1, and wherein at listone conjugated organic component out of Core3 and Core4 differs fromCore1 and Core2. Examples of the conjugated organic components Core1,Core2, Core3 and Core4 are given in Table 1, wherein the ionogenicside-groups G are selected from the list comprising —COOH, —SO₃H, and—H₂PO₃, k is equal 0, 1 or 2, p is equal to 1, 2 or 3.

In one embodiment of the disclosed optical film, the ionogenicside-groups provide a solubility of the organic compound of the firsttype or its salts in water and are the same or different andindependently selected from the list comprising —COOH, —SO₃H, and—H₂PO₃.

In one embodiment the organic compounds of the first type of the generalstructural formula [I] is selected from structures 3 to 13 given inTable 2, wherein the ionogenic side-group G is sulfonic group —SO₃H, andk is equal to 0, 1 or 2.

In still another embodiment of the disclosed optical film, the organiccompound of the first type further comprises additional side-groupsindependently selected from the list comprising linear and branched (C₁C₂₀)alkyl, (C₂-C₂₀)alkenyl, and (C₂-C₂₀)alkinyl

In yet another embodiment of the disclosed optical film, at least one ofthe additional side-groups of the organic compound of the first type isconnected with the Core via a bridging group A selected from the listcomprising —C(O)—, —C(O)O—, —C(O)—NH—, —(SO₂)NH—, —O—, —CH₂O—,—NH—, >N—, and any combination thereof. In one embodiment of thedisclosed optical film, the salt of the organic compound of the firsttype is selected from the list comprising ammonium and alkali-metalsalts.

In still another embodiment of the disclosed optical film, at leastpartially conjugated substantially planar polycyclic molecular systemsSys of the organic compound of the second type represented by thegeneral structural formula (II) is selected from structures 14 to 27given in Table 3.

In another embodiment the organic compounds of the second type of thegeneral structural formula (II) is selected from structures 28 to 35given in Table 4, where the molecular systems Sys are represented by thestructures 14 and 21 to 27, the substituent is sulfonic group —SO₃H; andm, p, v, and w are equal to 0.

In one embodiment of the present invention, the optical film furthercomprises inorganic compounds which are selected from the listcomprising hydroxides and salts of alkali metals.

In another embodiment of the disclosed optical film, the solidretardation layer is generally a biaxial retardation layer possessingtwo refractive indices (n_(x) and n_(y)) corresponding to two mutuallyperpendicular directions in the plane of the substrate front surface andone refractive index (n_(z)) in the normal direction to the substratefront surface, and wherein the refractive indices obey the followingcondition: n_(x)≠n_(z)≠n_(y).

In still another embodiment of the disclosed optical film, the solidretardation layer is retardation layer which type and degree ofbiaxiality is predetermined via controlling molar ratio of compositionof the organic compounds of the first and the second type. In oneembodiment of the disclosed optical film, the refractive indices of saidretardation layer obey the following condition: n_(x)<n_(y)<n_(x). Inanother embodiment of the disclosed optical film, the refractive indicesof said retardation layer obey the following condition:n_(x)<n_(z)<n_(y).

In another preferred embodiment the substrate is transparent toelectromagnetic radiation in the visible spectral range. The substratemay comprise a polymer, for example PET (polyethylene terephthalate) orTAC (triacetyl cellulose). In alternative embodiment of the disclosedoptical film, the substrate comprises a glass. In one embodiment of thedisclosed optical film, the transmission coefficient of the substratedoes not exceed 2% at any wavelength in the UV spectral range. Inanother embodiment of the optical film, the transmission coefficient ofthe substrate in the visible spectral range is not less than 90%.

In one embodiment of the disclosed invention, the optical film furthercomprises a protective coating formed on the adhesive transparent layer.

In one embodiment of the optical film, the substrate is a specular ordiffusive reflector.

In another embodiment of the optical film, the substrate is a reflectivepolarizer. In still another embodiment, the optical film furthercomprises a planarization layer deposited onto the front surface of thesubstrate. In yet another embodiment of the invention, the optical filmfurther comprises an additional transparent adhesive layer placed on topof the organic layer. In another possible embodiment of the invention,the optical film further comprises an additional transparent adhesivelayer placed on top of the optical film. In one embodiment of thedisclosed invention, the optical film further comprises a protectivecoating formed on the adhesive transparent layer. In one embodiment ofthe disclosed optical film comprising an adhesive layer, thetransmission coefficient of the adhesive layer does not exceed 2% at anywavelength in the UV spectral range. In another embodiment of thedisclosed optical film, the transmission coefficient of the adhesivelayer in the visible spectral range is not less than 90%.

In yet further aspect, the present invention provides a method ofproducing an optical film, comprising the steps of

-   -   a) preparation of a lyotropic liquid crystal solution of a        composition comprising at least one organic compound of a first        type, and at least one organic compound of a second type,        wherein the organic compound of the first type has a general        structural formula I

where Core is a conjugated organic unit capable of forming a rigidrod-like macromolecule, n is a number of the conjugated organic units inthe rigid rod-like macromolecule, Gk is a set of ionogenic side-groups,and k is a number of the side-groups in the set Gk; the ionogenicside-groups and the number k provide solubility of the organic compoundof the first type in the solvent and give rigidity to the rod-likemacromolecule; and the number n provides molecule anisotropy thatpromotes self-assembling of the macromolecules in a solution of theorganic compound or its salt, andwherein the organic compound of the second type has a general structuralformula II

where Sys is an at least partially conjugated substantially planarpolycyclic molecular system; X, Y, Z and Q are substituents; substituentX is a carboxylic group —COOH, substituent Y is a sulfonic group —SO₃H,substituent Z is a carboxamide, substituent Q is a sulfonamide, and m,h, p, v are 0, 1, 2, 3, or 4, wherein the organic compound of the secondtype is capable of forming board-like supramolecules viaπ-π-interaction; and wherein the composition of the organic compounds ofthe first and the second type or their salts is capable of forming alyotropic liquid crystal solution;

-   -   b) application of a liquid layer of the solution onto a        substrate, wherein the liquid layer is substantially transparent        to electromagnetic radiation in the visible spectral range;    -   c) application of an external alignment action onto said liquid        layer; and    -   d) drying to form a solid optical retardation layer.

In one embodiment of the disclosed method, the external alignment isapplied with a shear force, and with the increasing shear rate theviscosity of the solution decreases below approximately 200 mPa·s. Inanother embodiment of the disclosed method, the external alignment stepis performed simultaneously with the step of application of the liquidlayer to the substrate.

In one embodiment of the disclosed method, the number k is equal to 0,1, 2, 3, 4, 5, 6, 7, or 8, and the number n is an integer in the rangefrom 10 to 10000. In another embodiment of the disclosed method, theorganic compound of the first type has a polymeric main rigid-chain,wherein the conjugated organic units are the same. In still anotherembodiment of the disclosed method, the organic compound of the firsttype has a copolymeric main rigid-chain, wherein at least one conjugatedorganic unit is different from others. In one embodiment of thedisclosed method, the number k is more than 1, and the ionogenicside-groups are the same. In another embodiment of the disclosed method,the number k is more than 1, and at least one said ionogenic side-groupis different from others. In still another embodiment of the disclosedmethod, at least one conjugated organic unit (Core) of the organiccompound of the first type has a general structural formula III-(Core1)-S1-(Core2)-S2-   (III)wherein Core1 and Core2 are conjugated organic components, and spacersS1 and S2 are selected independently from the list comprising —C(O)—NH—,—NH—C(O)—, —O—NH—, linear and branched (C₁-C₄)alkylenes, linear andbranched (C₁-C₄)alkenylenes, —O—CH₂—, —CH₂—O—, —CH═CH—, —CH═CH—C(O)O—,—O(O)C—CH═CH—, —C(O)—CH₂—, —OC(O)—O—, —OC(O)—, —C≡C—, —C(O)—S—, —S—,—S—C(O)—, —O—, —NH—, —N(CH₃)—. In yet another embodiment of thedisclosed method, at least one rigid-core polymer is copolymer havingthe general structural formula IV[-(Core1)-S1-(Core2)-S2]_(n-t)[-(Core3)-S3-[(Core4)-S4-]_(j)]_(t)   (IV)wherein Core1, Core2, Core3 and Core4 are conjugated organic components,spacers S1, S2, S3 and S4 are selected independently from the list—C(O)—NH—, —NH—C(O)—, —O—NH , linear and branched (C₁-C₄)alkylenes,linear and branched (C₁-C₄)alkenylenes, (C₂-C₂₀)polyethylene glycols,—O—CH₂—, —CH₂—O—, —CH═CH—, —CH═CH—C(O)O—, —O(O)C—CH═CH—, —C(O)—CH₂—,—OC(O)—O—, —OC(O)—, —C≡C—, —C(O)—S—, —S—, —S—C(O)—, —O—, —NH—, —N(CH₃)—,n is an integer in the range from 10 to 10000, t is an integer in therange from 1 to n−1 and j is 0 or 1, and wherein at list one conjugatedorganic component out of Core3 and Core4 differs from Core1 and Core2.Examples of the conjugated organic components Core1, Core2, Core3 andCore4 are given in Table 1, wherein the ionogenic side-groups G areselected from the list comprising —COOH, —SO₃H, and —H₂PO₃, k is equal0, 1 or 2, p is equal to 1, 2 or 3.

In one embodiment of the disclosed method, the ionogenic side-groupsprovide a solubility of the organic compound of the first type or itssalts in water and are the same or different and independently selectedfrom the list comprising —COOH, —SO₃H, and —H₂PO₃.

In one embodiment the organic compounds of the first type of the generalstructural formula (I) is selected from structures 3 to 13 given inTable 2, wherein the ionogenic side-group G is sulfonic group —SO₃H, andk is equal to 0, 1 or 2.

In still another embodiment of the disclosed method, the organiccompound of the first type further comprises additional side-groupsindependently selected from the list comprising linear and branched(C₁-C₂₀)alkyl, (C₂-C₂₀)alkenyl, and (C₂-C₂₀)alkinyl

In yet another embodiment of the disclosed method, at least one of theadditional side-groups of the organic compound of the first type isconnected with the Core via a bridging group A selected from the listcomprising —C(O)—, —C(O)O—, —C(O)—NH—, —(SO₂)NH—, —O—, —CH₂O—,—NH—, >N—, and any combination thereof. In one embodiment of thedisclosed method, the salt of the organic compound of the first type isselected from the list comprising ammonium and alkali-metal salts.

In another embodiment at least partially conjugated substantially planarpolycyclic molecular systems Sys of the organic compound of the secondtype is selected from structures 14 to 27 given in Table 3.

In still further embodiment of the disclosed method, the organiccompounds of the second type of the general structural formula (II) isselected from structures 28 to 35 given in Table 4, where the molecularsystems Sys are represented by the structures 14 and 21 to 27, thesubstituent is sulfonic group —SO₃H; and m, p, v, and w are equal to 0.

In one embodiment of the disclosed method, the solvent is selected fromthe list comprising water, alkalis and acids or any combination thereof.In another embodiment of the disclosed method, the organic solvent isselected from the list comprising ketones, carboxylic acids,hydrocarbons, cyclohydrocarbons, chlorohydrocarbons, alcohols, ethers,esters, and any combination thereof. In a preferred embodiment of thedisclosed method, the organic solvent is selected from the listcomprising acetone, xylene, toluene, ethanol, methylcyclohexane, ethylacetate, diethyl ether, octane, chloroform, methylenechloride,dichloroethane, trichloroethene, tetrachloroethene, carbontetrachloride, 1,4-dioxane, tetrahydrofuran, pyridine, triethylamine,nitromethane, acetonitrile, dimethylformamide, dimethulsulfoxide, andany combination thereof.

In one embodiment of the disclosed method, the salt is selected from thelist comprising alkali-metal salts and ammonium salt. In the disclosedmethod the lyotropic liquid crystal may further comprise inorganiccompounds which are selected from the list comprising hydroxides andsalts of alkali metals.

In another embodiment of the disclosed method, the substrate is made ofa material selected from the list comprising a polymer and a glass. Inthe present invention, the disclosed method may further comprise apost-treatment step comprising a post-treatment with a solution of anwater-soluble inorganic salt comprising a cation selected from the listcomprising H⁺, Ba²⁺, Pb²⁺, ca²⁺, Mg²⁺, Sr²⁺, La³⁺, Zn²⁺, Zr⁴⁺, Ce³⁺,Y³⁺, Yb³⁺, Gd³⁺ and any combination thereof.

In one embodiment of the disclosed method, the application of the liquidlayer to the substrate step and post-treatment step are carried outsimultaneously. In another embodiment of the disclosed method, thedrying and post-treatment steps are carried out simultaneously. In stillanother embodiment of the disclosed method, the post-treatment step iscarried out after drying.

In still another embodiment of the disclosed method, the alignmentaction on the deposited liquid layer is performed with use of equipmentselected from the list comprising Mayer rod, slot die, extrusion, rollcoating, curtain coating, knife coating and molding. In one embodimentof the disclosed method, the external alignment action on the depositedlayer is performed with the use of mechanical translation over the layerof at least one aligning tool and the distance from the substratesurface to the edge or the plane of the aligning tool is set so as toobtain desired film thickness. In this method, the aligning tool may beheated.

In another embodiment of the disclosed method, the drying step isexecuted in airflow and/or at elevated temperature.

In still another embodiment of the present invention, the disclosedmethod further comprises a pretreatment step which takes place beforethe application onto the substrate. The pretreatment step may comprisethe step of making the surface of the substrate hydrophilic. In anotherembodiment of this method, the pretreatment further comprisesapplication of a planarization layer. In yet another embodiment of thedisclosed method, the sequence of the technological steps is repeatedtwo or more times and the solution used in the fabrication of eachsubsequent solid retardation layer is either the same or different fromthat used in the previous cycle.

In still further aspect, the present invention provides a liquid crystaldisplay comprising a vertical alignment mode liquid crystal cell, twopolarizers arranged on each side of the liquid crystal cell, and atleast one compensating structure located between said polarizers,wherein the polarizers have transmission axes which are perpendicular toeach other, and the compensating structure comprises at least oneretardation layer, wherein the retardation layer comprises at least oneorganic compound of the first type and at least one organic compound ofthe second type, wherein the organic compound of the first type has ageneral structural formula I

where Core is a conjugated organic unit capable of forming a rigidrod-like macromolecule, n is a number of the conjugated organic units inthe rigid rod-like macromolecule, Gk is a set of ionogenic side-groups,and k is a number of the side-groups in the set Gk; the ionogenicside-groups and the number k provide solubility of the organic compoundof the first type in the solvent and give rigidity to the rod-likemacromolecule; the number n provides molecule anisotropy that promotesself-assembling of the macromolecules in a solution of the organiccompound or its salt, and wherein the organic compound of the secondtype has a general structural formula II

where Sys is an at least partially conjugated substantially planarpolycyclic molecular system; X, Y, Z and Q are substituents; substituentX is a carboxylic group —COOH, substituent Y is a sulfonic group —SO₃H,substituent Z is a carboxamide —CONH₂, substituent Q is a sulfonamide—SO₂NH₂, and m, h, p, v are 0, 1, 2, 3, or 4; wherein the organiccompound of the second type is capable of forming board-likesupramolecules via π-π-interaction; wherein the composition of theorganic compounds of the first and the second type or their salts iscapable of forming a lyotropic liquid crystal solution; and wherein thesolution is capable of forming a solid retardation layer of biaxial typesubstantially transparent to electromagnetic radiation in the visiblespectral range.

In one embodiment of the disclosed liquid crystal display, the number kis equal to 0, 1, 2, 3, 4, 5, 6, 7, or 8, and the number n is an integerin the range from 10 to 10000. In another embodiment of the disclosedliquid crystal display, the organic compound of the first type has apolymeric main rigid-chain, wherein the conjugated organic units are thesame. In still another embodiment of the disclosed liquid crystaldisplay, the organic compound of the first type has a copolymeric mainrigid-chain, wherein at least one conjugated organic unit is differentfrom others. In one embodiment of the disclosed liquid crystal display,the number k is more than 1, and the ionogenic side-groups are the same.In another embodiment of the disclosed liquid crystal display, thenumber k is more than 1, and at least one said ionogenic side-group isdifferent from others.

In still another embodiment of the disclosed liquid crystal display, atleast one conjugated organic unit (Core) of the organic compound of thefirst type has a general structural formula III-(Core1)-S1-(Core2)-S2-   (III)wherein Core1 and Core2 are conjugated organic components, and spacersS1 and S2 are selected independently from the list —C(O)—NH—, —NH—C(O)—,—O—NH—, linear and branched (C₁-C₄)alkylenes, linear and branched(C₁-C₄)alkenylenes, —O—CH₂—, —CH₂—O—, —CH═CH—, —CH═CH—C(O)O—,—O(O)C—CH═CH—, —C(O)—CH₂—, —OC(O)—O—, —OC(O)—, —C≡C—, —C(O)—S—, —S—,—S—C(O)—, —O—, —NH—, —N(CH₃)—. In yet another embodiment of thedisclosed liquid crystal display, at least one rigid-core polymer iscopolymer having the general structural formula IV[-(Core1)-S1-(Core2)-S2]_(n-t)[-(Core3)-S3-[(Core4)-S4-]_(j)]_(t)   (IV)wherein Core1, Core2, Core3 and Core4 are conjugated organic components,spacers S1, S2, S3 and S4 are selected independently from the listcomprising —C(O)—NH—, —NH—C(O)—, —O—NH—, linear and branched (C₁-C₄)alkylenes, linear and branched (C₁-C₄)alkenylenes, (C₂-C₂₀) polyethyleneglycols, —O—CH₂—, —CH₂—O—, —CH═CH—, —CH═CH—C(O)O—, —O(O)C—CH═CH—,—C(O)—CH₂—, —OC(O)—O—, —OC(O)—, —C≡C—, —C(O)—S—, —S—, —S—C(O)—, —O—,—NH—, —N(CH₃)—, n is an integer in the range from 10 to 10000, t is aninteger in the range from 1 to n−1 and j is 0 or 1, and wherein at listone conjugated organic component out of Core3 and Core4 differs fromCore1 and Core2. Examples of the conjugated organic components Core1,Core2, Core3 and Core4 are given in Table 1, wherein the ionogenicside-groups G are selected from the list comprising —COOH, —SO₃H, and—H₂PO₃, k is equal 0, 1 or 2, p is equal to 1, 2 or 3.

In one embodiment of the disclosed liquid crystal display, the ionogenicside-groups provide a solubility of the organic compound of the firsttype or its salts in water and are the same or different andindependently selected from the list comprising —COOH, —SO₃H, and—H₂PO₃.

In one embodiment the organic compounds of the first type of the generalstructural formula [I] is selected from structures 3 to 13 given inTable 2, wherein the ionogenic side-group G is sulfonic group —SO₃H, andk is equal to 0, 1 or 2.

In still another embodiment of the disclosed liquid crystal display, theorganic compound of the first type further comprises additionalside-groups independently selected from the list comprising linear andbranched (C₁-C₂₀)alkyl, (C₂-C₂₀)alkenyl, and (C₂-C₂₀)alkinyl

In yet another embodiment of the disclosed liquid crystal display, atleast one of the additional side-groups of the organic compound of thefirst type is connected with the Core via a bridging group A selectedfrom the list comprising —C(O)—, —C(O)O—, —C(O)—NH—, —(SO₂)NH—, —O—,—CH₂O—, —NH—, >N—, and any combination thereof. In one embodiment of thedisclosed liquid crystal display, the salt of the organic compound ofthe first type is selected from the list comprising ammonium andalkali-metal salts.

In still another embodiment of the disclosed liquid crystal display, atleast partially conjugated substantially planar polycyclic molecularsystems Sys of the organic compound of the second type represented bythe general structural formula (II) is selected from structures 14 to 27given in Table 3.

In another possible embodiment the organic compounds of the second typeof the general structural formula (II) is selected from structures 28 to35 given in Table 4, where the molecular systems Sys are represented bythe structures 14 and 21 to 27, the substituent is sulfonic group —SO₃H;and m, p, v, and w are equal to 0.

In one embodiment of the present invention, the liquid crystal displayfurther comprises inorganic compounds which are selected from the listcomprising hydroxides and salts of alkali metals.

In one embodiment of the disclosed liquid crystal display, thecompensating structure comprises the single retardation layer which ischaracterized by two in-plane refractive indices (nf and ns)corresponding to a fast principal axis and a slow principal axisrespectively, and one refractive index (nn) in the normal directionwhich obey the following conditions for electromagnetic radiation in thevisible spectral range: ns>nf>nn.

In another embodiment of the disclosed liquid crystal display, at leastone compensating structure is located between the liquid crystal celland one of said polarizers. In yet another embodiment of the disclosedliquid crystal display, at least one compensating structure is locatedinside the liquid crystal cell. In still another embodiment of thedisclosed liquid crystal display, at least two compensating structureslocated on each side of the liquid crystal cell.

In one embodiment of the present invention, a liquid crystal displayfurther comprises an additional retardation layer which is characterizedby two in-plane refractive indices (nf and ns) corresponding to a fastprincipal axis and a slow principal axis respectively, and onerefractive index (nn) in the normal direction which obey the followingconditions for electromagnetic radiation in the visible spectral range:ns=nf>nn. In still another embodiment of the disclosed liquid crystaldisplay, at least one of the two polarizers comprises at least oneretardation TAC-layer.

In order that the invention may be more readily understood, reference ismade to the following examples, which are intended to be illustrative ofthe invention, but are not intended to be limiting the scope.

EXAMPLES Example 1

This Example describes synthesis of poly(2,2′-disulfo-4,4′-benzidineterephthalamide) cesium salt (structure 3 in Table 2).

1.377 g (0.004 mol) of 4,4′-diaminobiphenyl-2,2′-disulfonic acid wasmixed with 1.2 g (0.008 mol) of Cesium hydroxide and 40 ml of water andstirred with dispersing stirrer till dissolution. 0.672 g (0.008 mol) ofsodium bicarbonate was added to the solution and stirred. While stirringthe obtained solution at high speed (2500 rpm) the solution of 0.812 g(0.004 mol) of terephthaloyl dichloride in dried toluene (15 mL) wasgradually added within 5 minutes. The stirring was continued for 5 moreminutes, and viscous white emulsion was formed. Then the emulsion wasdiluted with 40 ml of water, and the stirring speed was reduced to 100rpm. After the reaction mass has been homogenized the polymer wasprecipitated via adding 250 ml of acetone. Fibrous sediment was filteredand dried.

Gel permeation chromatography (GPC) analysis of the sample was performedwith Hewlett Packard 1050 chromatograph with diode array detector (λ=230nm), using Varian GPC software Cirrus 3.2 and TOSOH Bioscience TSKgelG5000 PW_(XL) column and 0.2 M phosphate buffer (pH=7) as the mobilephase. Poly(para-styrenesulfonic acid) sodium salt was used as GPCstandard. The number average molecular weight Mn, weight averagemolecular weight Mw, and polydispersity P were found as 3.9×10⁵,1.7×10⁶, and 4.4 respectively.

Example 2

This Example describes synthesis of poly(2,2′-disulfo-4,4′-benzidinesulfoterephthalamide) (structure 4 in Table 2).

10 g (40 mmol) of 2-sulfoterephtalic acid, 27.5 g (88.7 mmol) oftriphenylphosphine, 20 g of Lithium chloride and 50 ml of pyridine weredissolved in 200 ml of N-methylpyrrolidone in a 500 ml three-neckedflask. The mixture was stirred at 40° C. for 15 min and then 13.77 g (40mmol) of 4,4′-diaminobiphenyl-2,2′-disulfonic acid were added. Thereaction mixture was stirred at 115° C. for 3 hours. 1 L of methanol wasadded to the viscous solution, formed yellow precipitate was filtratedand washed sequentially with methanol (500 ml) and diethyl ether (500ml). Yellowish solid was dried in vacuo at 80° C. overnight. Molecularweight analysis of the sample via GPC was performed as described inExample 1.

Example 3

This Example describes synthesis of poly(para-phenylenesulfoterephthalamide) (structure 5 in Table 2).

10 g (40 mmol) of 2-sulfoterephtalic acid, 27.5 g (88.7 mmol) oftriphenylphosphine, 20 g of Lithium chloride and 50 ml of pyridine weredissolved in 200 ml of N-methylpyrrolidone in a 500 ml three-neckedflask. The mixture was stirred at 40° C. for 15 min and then 4.35 g (40mmol) of 1,4-phenylenediamine were added. The reaction mixture wasstirred at 115° C. for 3 hours. 1 L of methanol was added to the viscoussolution, formed yellow precipitate was filtrated and washedsequentially with methanol (500 ml) and diethyl ether (500 ml).Yellowish solid was dried in vacuo at 80° C. overnight. Molecular weightanalysis of the sample via GPC was performed as described in Example 1.

Example 4

This Example describes synthesis of poly(2-sulfo-1,4-phenylenesulfoterephthalamide) (structure 6 in Table 2).

10 g (40 mmol) of 2-sulfoterephtalic acid, 27.5 g (88.7 mmol) oftriphenylphosphine, 20 g of Lithium chloride and 50 ml of pyridine weredissolved in 200 ml of N-methylpyrrolidone in a 500 ml three-neckedflask. The mixture was stirred at 40° C. for 15 min and then 7.52 g (40mmol) of 2-sulfo-1,4-phenylenediamine were added. The reaction mixturewas stirred at 115° C. for 3 hours. 1 L of methanol was added to theviscous solution, formed yellow precipitate was filtrated and washedsequentially with methanol (500 ml) and diethyl ether (500 ml).Yellowish solid was dried in vacuo at 80° C. overnight. Molecular weightanalysis of the sample via GPC was performed as described in Example 1.

Example 5

This Example describes synthesis of poly(2,2′-disulfo-4,4′-benzidinenaphthalene-2,6-dicarboxamide) cesium salt (structure 7 in Table 2).

0.344 g (0.001 mol) of 4,4′-diaminobiphenyl-2,2′-disulfonic acid wasmixed with 0.3 g (0.002 mol) of Cesium hydroxide and 10 ml of water andstirred with dispersing stirrer till dissolution. 0.168 g (0.002 mol) ofsodium bicarbonate was added to the solution and stirred. While stirringthe obtained solution at high speed (2500 rpm) the solution of 0.203 g(0.001 mol) of terephthaloyl dichloride in dried toluene (4 mL) wasgradually added within 5 minutes. The stirring was continued for 5 moreminutes, and viscous white emulsion was formed. Then the emulsion wasdiluted with 10 ml of water, and the stirring speed was reduced to 100rpm. After the reaction mass has been homogenized the polymer wasprecipitated via adding 60 ml of acetone. The fibrous sediment wasfiltered and dried. Molecular weight analysis of the sample via GPC wasperformed as described in Example 1.

Example 6

This Example describes synthesis of4,4′-(5,5-dioxidodibenzo[b,d]thiene-3,7-diyl)dibenzenesulfonic acid(structure 28 in Table 4).

1,1′:4′,1″:4″,1′″-quarerphenyl (10 g) was charged into 0%-20% oleum (100ml). Reaction mass was agitated for 5 hours at heating to 50° C. Afterthat the reaction mixture was diluted with water (170 ml). The finalsulfuric acid concentration became approximately 55%. The precipitatewas filtered and rinsed with glacial acetic acid (˜200 ml). The filtercake was dried in an oven at 110° C.

HPLC analysis of the sample was performed with Hewlett Packard 1050chromatograph with diode array detector (λ=310 nm), using Reprosil™ GoldC8 column and linear gradient elution with acetonitrile/0.4 M ammoniumacetate (pH=3.5 acetic acid) aqueous solution.

Example 7

This example describes synthesis ofpoly(disulfobiphenylene-1,2-ethylene-2,2′-disulfobiphenylene) (structure8 in Table 2).

Copper(I) bromide (0.3 g) was added to a suspension of iron powder (1.2g) in water (30 mL). Then suspension was agitated at a room temperaturefor 20 min, the resulting mixture was heated up to 90° C. 4-Bromobenzylbromide (10 g) was added by portions to the reaction mixture, and themixture was stirred at 90° C. for 2 hours. After the mixture was cooledto the room temperature, the solid was filtered off and washed with hotwater. Filter cake was dissolved in the boiling methanol. Hot solutionwas filtered and cooled to the room temperature.

Precipitate was filtered and dried on air. Yield 2.5 g.

5.4 ml of 2.5 M solution of butyllithium in hexane was added dropwise toa stirred solution of 3 g of 4,4′-dibromobibenzyl in 100 ml of drytetrahydrofuran under argon at ±78° C. The mixture was stirred at thistemperature for 6 hrs and a white suspension was received. 6 ml oftriisopropylborate was added and the mixture was stirred overnightallowing the temperature to rise to room temperature. 30 ml of water wasadded and the mixture was stirred at room temperature for 4 hrs. Theorganic solvents were removed on a rotavapor (35° C., 40 mbar), then 110ml of water was added and a mixture was acidified with concentrated HCl.The product was extracted into diethyl ether (7×30 ml), the organiclayer dried over magnesium sulfate and the solvent was removed on arotavapor. The residue was dissolved in 11 ml of acetone andreprecipitated into a mixture of 13 ml of water and 7 ml of concentratedhydrochloric acid. The yield of dipropyleneglycol ester of bibenzyl4,4′-diboronic acid is 2.4 g.

100 g of 4,4′-diamino-2,2′-biphenyldisulfonic acid, 23.2 g of sodiumhydroxide and 3.5 L of water were mixed and cooled down to 0-5° C. Asolution of 41 g of sodium nitrite in 300 ml of water was added, stirredfor 5 min and then 100 ml of 6M hydrochloric acid was added to thesolution. A pre-cooled solution of 71.4 g of potassium bromide in 300 mlof water was added to the resulting dark yellow solution in 2 mlportions. After potassium bromide was added the solution was allowed towarm up to room temperate. Then the reaction mixture was heated and heldat 90° C. for 16 hours. A solution of 70 g of sodium hydroxide in 300 mlof water was added, the solution evaporated to a total volume of 400 ml,diluted with 2.5 L of methanol to precipitate the inorganic salts andfiltered. Methanol was evaporated to 20-30 ml and 3 L of isopropanol wasadded. The precipitate was washed with methanol on a filter andrecrystallized from methanol. Yield of4,4′-dibromo-2,2′-biphenyldisulfonic acid was 10.7 g.

Polymerization was carried out under nitrogen. 2.7 g of4,4′-dihydroxy-2,2′-biphenyldisulfonic acid and 2.0 g ofdipropyleneglycol ester of bibenzyl 4,4′-diboronic acid were dissolvedin a mixture of 2.8 g of sodium hydrocarbonate, 28.5 ml oftetrahydrofuran and 17 ml of water.Tetrakis(triphenylphosphine)palladium(0) was added (5×10⁻³ molarequivalent compared to dipropyleneglycol ester of bibenzyl4,4′-diboronic acid). The resulting suspension was stirred for 20 hrs.0.04 g of bromobenzene was then added. After an additional 2 hrs apolymer was precipitated by pouring it into 150 ml of ethanol. Theproduct was washed with water, dried and dissolved in toluene. Afiltered solution was concentrated and a polymer was precipitated in a5-fold excess of ethanol and dried. The yield of polymer was 2.7 g.

8.8 g of 95% sulfuric acid was heated to 110° C. and 2.7 g of thepolymer was added. Temperature was raised to 140° C. and was held for 4hours. After cooling down to 100° C. 8 ml of water was added dropwiseand mixture was allowed to cool. A resulting suspension was filtered,washed with concentrated hydrochloric acid and dried. The yield of thesulfonated polymer was ˜2 g.

Example 8

This example describes synthesis ofpoly(2,2′-disulfobiphenyl-dioxyterephthaloyl) (structure 9 in Table 2).

1.384 g (0.004 mol) of 4,4′-dihydroxybiphenyl-2,2′-disulfonic acid wasmixed with 2.61 g (0.008 mol) of sodium carbonate and 40 ml of water in500 ml beaker and stirred with dispersing stirrer until the solid wascompletely dissolved. Dichloromethane (50 ml) was added to the solution.Upon stirring at high speed (7000 rpm) the solution of 0.812 g (0.004mol) of terephthaloyl chloride in anhydrous dichloromethane (15 ml) wasadded. Stirring was continued for 30 minutes and 400 ml of acetone wereadded to the thickened reaction mass. Solid polymer was crushed with thestirrer and separated by filtration. The product was washed three timeswith 80% ethanol and dried at 50° C.

Example 9

This example describes synthesis ofpoly(2,2′-disulfobiphenyl-2-sulfodioxyterephthaloyl) (structure 10 inTable 2).

1.384 g (0.004 mol) of 4,4′-dihydroxybiphenyl-2,2′-disulfonic acid wasmixed with 3.26 g (0.010 mol) of sodium carbonate and 40 ml of water in500 ml beaker and stirred with dispersing stirrer until the solidcompletely dissolved. Dichloromethane (60 ml) was added to the solution.Upon stirring at high speed (7000 rpm) 1.132 g (0.004 mol) of2-sulfoterephthaloyl chloride was added within 15 minutes. Stirring wascontinued for 3 hours and 400 ml of acetone were added to the thickenedreaction mass. Precipitated polymer was separated by filtration anddried at 50° C.

Example 10

This example describes synthesis ofpoly(sulfophenylene-1,2-ethylene-2,2′-disulfobiphenylene) (structure 11in Table 2).

The 4,4′-dibromobibenzyl was prepared as described in Example 7.

A solution of 23.6 g of 1,4-Dibromobenzene in 90 ml of drytetrahydrofuran was prepared. 10 ml of the solution was added withstirring to 5.0 g of magnesium chips and iodine (a few crystals) in 60ml of dry tetrahydrofuran and a mixture was heated until reactionstarts. Boiling conditions were maintained by the gradual addition ofthe rest of dibromobenzene solution. Then the reaction mixture wasboiled for 8 hours and left overnight under argon at room temperature.The mixture was transferred through a hose to a dropping funnel by meansof argon pressure and added to a solution of 24 ml of trimethylborate in40 ml of dry tetrahydrofuran during 3 h at −78-70° C. (solid carbondioxide/acetone bath) and vigorous stirring. The mixture was stirred for2 hrs, then allowed to heat to room temperature with stirring overnightunder argon. The mixture was diluted with 20 ml of ether and was pouredto a stirred mixture of crushed ice (200 g) and conc. H₂SO₄ (6 ml). Inorder to facilitate the separation of organic and aqueous layers theamounts of 20 ml of ether and 125 ml of water was added to the mixtureand than the mixture was filtered. The aqueous layer was extracted withether (4×40 ml), the combined organic extracts were washed with 50 ml ofwater, dried over sodium sulfate and evaporated to dryness. The lightbrown solid was dissolved in 800 ml of chloroform and clarified.

The chloroform solution was almost completely evaporated and theresidual solid was recrystallized from benzene. A white slightlyyellowish precipitate was filtered off and dried. The yield ofdipropyleneglycol ester of benzyne 1,4-diboronic acid was 0.74 g.

Polymerization was carried out under nitrogen. 2.7 g of4,4′-dibromo-2,2′-bibenzyl and 1.9 g of dipropyleneglycol ester ofbenzyne 1,4-diboronic acid were added to a mixture of 2.8 g of sodiumhydrocarbonate, 28.5 ml of tetrahydrofuran and 17 ml of water.Tetrakis(triphenylphosphine)palladium(0) was added (5×10⁻³ molarequivalent compared to dipropyleneglycol ester of benzyne 1,4-diboronicacid). The resulting suspension was stirred for 20 hrs. 0.04 g ofbromobenzene was then added. After 2 more hours the polymer wasprecipitated by pouring it into 150 ml of ethanol. The product waswashed with water, dried and dissolved in toluene. The filtered solutionwas concentrated and a polymer was precipitated in a 5-fold excess ofethanol and dried. The yield of polymer was 2.5 g.

8.8 g of 95% sulfuric acid was heated to 110° C. and 2.7 g of a polymerwas added. Temperature was raised to 140° C. and held for 4 hours. Aftercooling down to the room temperature 8 ml of water was added dropwiseand the mixture was allowed to cool. The resulting suspension wasfiltered, washed with concentrated hydrochloric acid and dried. Yield ofthe sulfonated polymer was 1.5 g.

Example 11

This example describes synthesis ofpoly(2-sulfophenylene-1,2-ethylene-2′-sulfophenylene) (structure 12 inTable 2).

Polymerization was carried out under nitrogen. 10.2 g of2,2′-[ethane-1,2-diylbis(4,1 -phenylene)]bis-1,3,2-dioxaborinane, 10.5 gof 1,1′-ethane-1,2-diylbis(4-bromobenzene) and 1 g oftetrakis(triphenylphosphine)palladium(0) were mixed under nitrogen.Mixture of 50 ml of 2.4 M solution of potassium carbonate and 300 ml oftetrahydrofuran was degassed by nitrogen bubbling. Obtained solution wasadded to the first mixture. After that a reaction mixture was agitatedat ±40° C. for 72 hours. The polymer was precipitated by pouring it into150 ml of ethanol. The product was washed with water and dried. Theyield of polymer was 8.7 g.

8.5 g of polymer was charged into 45 ml of 95% sulfuric acid. Reactionmass was agitated at ˜140° C. for 4 hours. After cooling down to theroom temperature 74 ml of water was added dropwise and the mixture wasallowed to cool. The resulting suspension was filtered, washed withconcentrated hydrochloric acid and dried. Yield of the sulfonatedpolymer was 8 g.

Example 12

This example describes synthesis ofpoly(2,2′-disulfobiphenyl-2-sulfo-1,4-dioxymethylphenylene) (structure13 in Table 2).

190 g of 4,4′-diaminobiphenyl-2,2′-disulfonic acid and 41.5 g of sodiumhydroxide were dissolved in 1300 ml of water. 1180 g of ice was chargedto the solution with stirring. Then 70.3 g of sodium nitrite, 230 ml ofsulfuric acid and 1180 ml of water was added to the reaction mass andstirred for 1 hr at temperature from −2 to 0° C. Then it was filteredand washed with 2.4 L of icy water. The filter cake was suspended in 800ml of water and heated to 100° C. Then water was distilled out untilabout ˜600 ml solution remained. 166 g of cesium hydroxide hydrate in110 ml of water was added to the solution. Then it was added to 6 L ofethanol, the resulting suspension was stirred at room temperature,filtered and a filter cake washed with 600 ml of ethanol and dried invacuum oven at 45° C. The yield of4,4′-dihydroxybiphenyl-2,2′-disulfonic acid was 230 g.

30 ml of 96% Sulfuric acid and 21 g of p-xylene were mixed, heated to100° C. and kept at temperature for 15 min. The reaction mass was cooledto room temperature, quenched with 50 g water and ice. The resultingsuspension was cooled to −10° C., filtered and the obtained filter cakewas washed with cold hydrochloric acid (15 ml of conc. acid and 10 ml ofwater). The precipitate was squeezed and recrystallized fromhydrochloric acid solution (40 ml of concentrated acid and 25 ml ofwater). The white substance was dried under vacuum at 90° C. The yieldof p-xylene sulfonic acid was 34 g.

A mixture of 35 ml of carbon tetrachloride, 2.5 g of p-xylene sulfonicacid, 4.8 g of N-bromosuccinimide and 0.16 g of benzoyl peroxide wereheated with agitation to boiling and held at temperature 60 min. Thenadditional 0.16 g of benzoyl peroxide was added and a mixture was keptboiling for additional 60 min. After cooling the product was extractedwith 45 ml of water and recrystallized form 20% hydrochloric acid. Theyield of 2,5-bis(bromomethyl)benzene sulfonic acid was approximately 1g.

0.23 g of 4,4′-dihydroxybiphenyl-2,2′-disulfonic acid, 1.2 ml ofo-dichlorobenzene, 0.22 g of 2,5-bis(bromomethyl) benzene sulfonic acid,1.2 ml of 10N sodium hydroxide, and 0.081 g of tetrabutylammoniumhydrogen sulfate were successively added to a 25-ml flask equipped witha condenser and nitrogen inlet-outlet. The reaction mixture was stirredat 80° C. under nitrogen. After 6 hrs of reaction the organic layer wasisolated and washed with water, followed by dilute hydrochloric acid,and once again with water. Then solution was added to methanol toprecipitate a white polymer. The polymer is then reprecipitated fromacetone and methanol.

Example 13

This example describes synthesis of copolymer of2,2′-disulfo-4,4′-benzidine terephthaloylchloride and polyethyleneglycol 400 (structure 3 in Table 2 added with chains of polyethyleneglycols, where M is hydrogen). 4,4′-diaminobiphenyl-2,2′-disulfonic acid(4.1 g) was mixed with Cesium hydroxide hydrate (4.02 g, 2.0 equiv) inwater (150 ml) in a 1 L beaker and stirred until the solid wascompletely dissolved. Cesium bicarbonate (3.9 g, 1.0 equiv) dissolved in10 ml of water was added to the solution and stirred with an electricmixer at room temperature during 1 min. Chloroform (40 ml) andpolyethylene glycol 400 (8.0 g) were added. Upon stirring at high speeda solution of terephthaloylchloride (2.42 g, 1.0 equiv) in 10 ml ofchloroform was added in one portion pouring from the beaker. Thereaction was left without stirring at ambient conditions for 30 minutes.300 ml of ethanol was added, thickened reaction mass was crushed withthe stirrer and polymer was filtered. The product was suspended in 200ml of 80% ethanol, stirred for 15 min and filtered. Washing with ethanolwas repeated one more time. The product was washed with 200 ml ofacetone in a similar way. Solid copolymer was dried at 85° C. for 14hrs.

The introduction of ethylene oxide fragment into rigid-core polymerallows modification of macromolecule elasticity, which in its turnimproves phases' coexistence in guest-host mixture.

Example 14

This Example describes preparation of a solid optical retardation layerof +A-type from a lyotropic liquid crystal solution ofpoly(2,2′-disulfo-4,4′-benzidine terephthalamide) (structure 3 in Table2) cesium salt.

Poly(2,2′-disulfo-4,4′-benzidine terephthalamide) was synthesized asdescribed in Example 1. The lyotropic liquid crystal solution wasprepared according to the following procedure: 1% water solution wasprepared, filtered from mechanical admixtures, and concentrated toapproximately 5.6 wt. % via evaporation. Typical polarized microscopyimage of LLC solution is presented in FIG. 1.

Fisher-brand microscope glass slides were treated with a 10% sodiumhydroxide solution for 30 min, followed by rinsing with deionized waterand drying in airflow with the aid of a compressor. The solution wasapplied onto the glass plate surface with a Mayer rod #4 moved at alinear velocity of ˜100 mm/s at room temperature of 23° C. and arelative humidity of 50%. The coated liquid layer of the solution wasdried at the same humidity and temperature.

In order to determine the optical characteristics of the solidretardation layer, the optical transmission and reflection spectra weremeasured in a wavelength range from approximately 400 to 700 nm using aCary 500 Scan spectrophotometer. The optical transmission of the solidretardation layer was measured using light beams linearly polarizedbeing parallel and perpendicular to the coating direction (T_(par) andT_(per), respectively), propagating in direction perpendicular to theretardation film plane. The optical reflection was measured usingS-polarized light propagating at an angle of 12 degree to the normal ofthe retardation film plane and polarized parallel and perpendicular tothe coating direction (R_(par) and R_(per), respectively). The phaseretardation of the retardation film samples was measured at incidentangles of 0, 30, 45 and 60 degrees using Axometrics Mueller Matrixpolarimeter. The obtained data were used to calculate the principalrefractive indices (n_(x), n_(y), and n_(z)) of the retardation film aspresented in FIG. 2. The obtained solid retardation layer wascharacterized as a positive A-plate (n_(x)=1.83, n_(y)=1.55, n_(z)=1.55at the wavelength λ=550 nm).

Example 15

This Example describes preparation of a solid optical retardation layerof B_(A)-type from a solution of4,4′-(5,5-dioxidodibenzo[b,d]thiene-3,7-diyl)dibenzenesulfonic acid(structure 28 in Table 4).

4,4′-(5,5-dioxidodibenzo[b,d]thiene-3,7-diyl)dibenzenesulfonic acid (1g) was obtained as described in Example 6, mixed with 5.8 g of distilledwater and 3.2 g of 20% aqueous solution of cesium hydroxide, and thenstirred at room temperature (23° C.) for approximately 1 hour until alyotropic liquid crystal solution was formed. The polarized microscopyimage of LLC solution is presented in FIG. 3.

The coatings were produced and optically characterized as described inExample 14. The principal refractive index spectral dependences of theretardation film are presented in FIG. 4. The obtained solid opticalretardation layer was characterized by the principle refractive indices,which obey the following condition: n_(x)<n_(z)<n_(y). NZ-factor at thewavelength λ=550 nm is about 0.4.

Example 16

This Example describes preparation of a solid optical retardation layerof −A-type from a solution of(4,4′-(5,5-dioxidodibenzo[b,d]thiene-3,7-diyl)dibenzenesulfonic acid(structure 28 in Table 4).

4,4′-(5,5-dioxidodibenzo[b,d]thiene-3,7-diyl)dibenzenesulfonic acid (1g) was obtained as described in Example 6, mixed with 8.5 g of distilledwater and 0.5 g of 20% aqueous solution of lithium hydroxide, and thenstirred at room temperature (23° C.) for approximately 1 hour until alyotropic liquid crystal solution was formed. Typical polarizedmicroscopy image of LLC solution is presented in FIG. 5.

The coatings were produced and optically characterized as described inExample 14. The principal refractive index spectral dependences arepresented in FIG. 6. The obtained solid optical retardation layer wascharacterized by the principle refractive indices, which obey thefollowing condition: n_(x)<n_(z)=n_(y). NZ-factor at the wavelengthλ=550 nm is about 0.

Example 17

This Example describes preparation of a solid optical retardation layerof A_(C)-type from a solution comprising a binary composition ofpoly(2,2′-disulfo-4,4′-benzidine terephthalamide) (structure 3 in Table2) acid denoted hereafter as P1, and(4,4′-(5,5-dioxidodibenzo[b,d]thiene-3,7-diyl)dibenzenesulfonic aciddenoted hereafter as C1 (structure 28 in Table 4). Said composition oforganic compounds is capable of forming a joint lyotropic liquid crystalsystem. The rigid rod-like macromolecules of P1 are capable of aligningtogether with π-π (stacks (columns) of board-like supramolecules C1.

The P1/C1=70/30 molar % composition was prepared as follows: 5.18 g(0.007 mol) of cesium salt of P1 was dissolved in 515 g of de-ionizedwater (conductivity ˜5 μSm/cm); the suspension was mixed with a magnetstirrer. After dissolution, the solution was filtered with thehydrophilic nylon filter with pore size of 45 μm. Separately, 1.59 g(0.003 mol) of C1 was dissolved in 50 g of de-ionized water; thesuspension was mixed with a magnet stirrer. While stirring, 3.75 ml(0.006 mol) of 20 wt. % CsOH was gradually added drop-by-drop intosuspension for approximately 15 minutes until a clear solution wasformed. Clear solutions of P1 and C1 were mixed together to form 575 gof a clear solution. This composition was concentrated on a rotaryevaporator in order to remove an excess of water and form 95 g of abinary composition representing a lyotropic liquid crystal (LLC)solution. The total concentration of composition (P1+C1) C_(TOT) wasequal to 8%. Typical polarized microscopy image of LLC solution ispresented in FIG. 7.

The coatings were produced and optically characterized as described inExample 14. Fisher brand microscope glass slides were prepared forcoating by soaking in a 10% NaOH solution for 30 min, followed byrinsing with deionized water, and drying in airflow with the compressor.At temperature of 22° C. and relative humidity of 55% the obtained LLCsolution was applied onto the glass panel surface with a Gardner® wiredstainless steel rod #8, which was moved at a linear velocity of about100 mm/s. The optical film was dried with a flow of the compressed air.Typical polarized microscopy image of the optical film is presented inFIG. 8. The polarized microscopy image of the optical film coated byslot-die technique is presented in FIG. 9.

The coatings were optically characterized as described in Example 14.The principal refractive index spectral dependences of the retardationfilm are presented in FIG. 10. Two principal directions for refractiveindices n_(x) and n_(y) belong to xy-plane coinciding with a plane ofthe retardation layer and one principal direction for refractive indexn_(z) coincides with a normal line to the compensation panel. Theobtained solid optical retardation layer was characterized by theprinciple refractive indices, which obey the following condition:n_(z)<n_(y)<n_(x). The NZ-factor at the wavelength λ=550 nm was equal toabout 1.5.

FIG. 11 shows principal refractive indices (n_(x), n_(y), and n_(z)) ofa solid optical retardation layer prepared from a solution comprising abinary composition of the compounds P1 and C1. The NZ-factor at thewavelength λ=550 nm was equal to about 2.0. In this case the ratio P1/C1was equal to 66/34 and total concentration of composition (P1+C1)C_(TOT) was equal to about 8%.

FIG. 12 shows principal refractive indices (n_(x), n_(y), and n_(z)) ofa solid optical retardation layer prepared from a solution comprising abinary composition of the compounds P1 and C1. The NZ-factor at thewavelength λ=550 nm was equal to about 3.0. In this case the ratio P1/C1was equal to about 60/40 and total concentration of composition (P1+C1)C_(TOT) was equal to about 8%.

Example 18

This Example describes the preparation of a solid optical retardationlayer of B_(A)-type from a solution comprising a composition of theorganic compounds P1 and C1 described in Example 17.

The P1/C1=38/62 molar % composition was prepared as follows: 2.81 g(0.0038 mol) of the cesium salt of P1 was dissolved in 70 g ofde-ionized water (conductivity ˜5 μSm/cm); the suspension was mixed witha magnet stirrer. After dissolution, the solution was filtered at thehydrophilic nylon filter with pore size 45 μm. Separately, 3.28 g(0.0062 mol) of C1 was dissolved in 103 g of de-ionized water;suspension was mixed with a magnet stirrer. While stirring, 7.75 ml of20 wt. % Cesium hydroxide was gradually added drop-by-drop into thesuspension for approximately 15 minutes until a clear solution wasformed. Clear solutions of P1 and C1 were mixed together to form 400 gof a clear solution. This composition was concentrated on a rotaryevaporator in order to remove an excess of water and form 70 g of abinary composition representing a lyotropic liquid crystal (LLC)solution. The total concentration of composition (P1+C1) C_(TOT) wasequal to about 11%.

The coatings were produced and optically characterized as described inExample 17. The principal refractive indices spectral dependences of asolid optical retardation layer prepared from a solution are presentedin FIG. 13. The obtained retardation layer was characterized by theprinciple refractive indices, which obey the following condition:n_(x)<n_(z)<n_(y). The NZ-factor at the wavelength λ=550 nm is equal toabout 0.75.

FIG. 14 shows principal refractive indices (n_(x), n_(y), and n_(z)) ofa solid optical retardation layer prepared from a solution comprising abinary composition of the compounds P1 and C1. NZ-factor at thewavelength λ=550 nm is equal to about 0.5. In this case the ratio P1/C1was equal to about 15/85 and total concentration of composition (P1+C1)C_(TOT) was equal to about 11%.

FIG. 15 shows principal refractive indices (n_(x), n_(y), and n_(z)) ofa solid optical retardation layer prepared from a solution comprising atriple composition of a cesium salt of compound P1 (“+A component”), acesium salt of compound C1 (“B_(A) component”) and a lithium salt ofcompound C1 (“−A component”), taken in molar ratio of approximately16/42/42. The NZ-factor at the wavelength λ=550 nm is equal to about0.3. The weight concentration of composition (P1+C1) C_(TOT) was about13%.

Example 19

This Example describes the preparation of a solid optical retardationlayer of −A-type from a solution comprising a binary composition of thesame organic compounds P1 and C1 as described in Example 17.

The P1/C1=15/85 molar % composition was prepared as follows: 1.48 g(0.002 mol) of the cesium salt of P1 was dissolved in 50 g of de-ionizedwater (conductivity ˜5 μSm/cm); the suspension was mixed with a magnetstirrer. After dissolution, the solution was filtered at the hydrophilicnylon filter with pore size 45 μm. Separately, 6.12 g (0.0113 mol) of C1compound was dissolved in 100 g of de-ionized water, and the suspensionwas mixed with a magnet stirrer. While stirring, 3.05 g of 20 wt. %Lithium hydroxide was gradually added drop-by-drop into the suspensionfor approximately 15 minutes until a clear solution was formed. Clearsolutions of P1 and C1 were mixed together to form 180 g of a clearsolution. This composition was concentrated on a rotary evaporator inorder to remove an excess of water and form 43 g of a binary compositionmaking a lyotropic liquid crystal (LLC) solution. The totalconcentration of composition (P1+C1) C_(TOT) was about 15%.

The coatings were produced and optically characterized, as was describedin Example 17. The principal refractive index spectral dependences of asolid optical retardation layer prepared from a solution are presentedin FIG. 16. The obtained solid optical retardation layer wascharacterized by the principle refractive indices, which obey thefollowing condition: n_(x)<n_(z)<n_(y). The NZ-factor at the wavelengthλ=550 nm is about 0.

Thus, the principle of the control of the retardation layer type isbased on mixing at least one component of the first type and at leastone component of the second type, wherein separately said components arecapable of forming optical retardation layers of different types.

The compound of the first type represents rigid polymeric moleculecapable of forming a lyotropic liquid crystal solution which is capableof forming an optical retardation layer of uniaxial +A-plate type (FIG.17a), wherein refractive indices n_(x1), n_(y1) and n_(z1) satisfy thefollowing condition:n_(x1)>n_(y1)=n_(z1)=n⊥₁.   (V)

The compound of the second type is capable of forming a lyotropic liquidcrystal solution which is capable of forming optical retardation layerof biaxial B_(A)-type (FIG. 17b) or uniaxial −A-type (FIG. 17c), whereinrefractive indices n_(x2), n_(y2) and n_(z2) satisfy the followingcondition:n_(x2)<n_(z2)≦n_(y2)   (VI)

When mixed, the joint LLC solution of guest-host type is formed. Thejoint LLC solution can be coated onto the substrate and being ordered bya shear stress in the same way as individual LLC solutions of thecompounds of the first and second types. In general case the joint LLCsolution forms an optical retardation layer of biaxial type (FIG. 17d).Correlation between the principal refractive indices of the solidoptical retardation layer is controlled by molar ratio of the componentsof the first and second types in the joint lyotropic liquid crystalsolution. The solution enriched with compound of the first type forms asolid retardation layer of A_(C)-type, and the solution enriched with acompound of the second type forms a solid retardation layer ofB_(A)-type. The NZ-factor of said solid retardation layer being variedin a wide range, wherein the lower limit is defined by the NZ-factor ofthe solid retardation layer formed by a compound of the second type.

On one hand the principal refractive indices n_(xi) correspond to thecoating direction, and on the other hand the principal refractiveindices n_(yi), and n_(zi) correspond to the orthogonal directions,which are in a plane perpendicular to the coating direction. Theprincipal refractive indices n_(x1) and n⊥₁ are controlled by a choiceof the organic compounds of the first type, and the principal refractiveindices n_(x2), n_(y2), and n_(z2) are controlled by a choice of theorganic compounds of the second type. Thus, a choice of the organiccompounds of the first and second types shown in Tables 2, 3 and 4, andthe molar ratio c allows preparing the optical film with a presetrelation of the principal refractive indices n_(x), n_(y) and n_(z).

The composition and method disclosed in the present invention allowindependently controlling three principal refractive indices of theoptical film. The principal refractive indices of the optical filmsatisfy the following conditions:

$\begin{matrix}\{ \begin{matrix}{n_{x} = {\sum\limits_{i = 1}^{N}\;{n_{xi} \cdot c_{i}}}} \\{n_{y} = {\sum\limits_{i = 1}^{N}\;{n_{yi} \cdot c_{i}}}} \\{n_{z} = {\sum\limits_{i = 1}^{N}\;{n_{zi} \cdot c_{i}}}}\end{matrix}  & ({VII})\end{matrix}$where N is number of components, n_(xi), n_(yi) and n_(zi) are theprincipal refractive indices corresponding to i-component, and c_(i) isa molar portion of i-component in a mixture, and wherein

${\sum\limits_{i = 1}^{N}\; c_{i}} = 1.$

Some particular cases are considered below.

A. A binary composition of one compound of the first type and onecompound of the second type, where the following condition is:n_(y1)=n_(z1)=n⊥₁<n_(x1) and n_(y2)=n_(z2)=n⊥₂>n_(x2).

The second compound forms negative A-type, but its slow indices are notequal to the slow indices of the positive A-type which is formed fromthe first compound. Then the relations (VII) will read

$\{ \begin{matrix}{n_{x} = {{c \cdot n_{x\; 1}} + {( {1 - c} ) \cdot n_{x\; 2}}}} \\{n_{y} = {n_{z} = {{c \cdot n}\bot_{1}{{+ ( {1 - c} )} \cdot n}\bot_{2}}}}\end{matrix}_{\;} $where N=2, c₁=c, c₂=1−c and c is a molar portion of the component of thefirst type.

When the molar ratio c is changed from 0 to 1, the type of theanisotropic optical film transforms from a negative A-type to a positiveA-type.

B. A binary composition of one compound of the first type and onecompound of the second type.

In this case the refractive indexes of the optical film satisfy thefollowing conditions:

$\begin{matrix}\{ \begin{matrix}{{n_{x} = {{c \cdot n_{x\; 1}} + {( {1 - c} ) \cdot n_{x\; 2}}}},} \\{{n_{y} = {{c \cdot n}\bot{{+ ( {1 - c} )} \cdot n_{y\; 2}}}},} \\{n_{z} = {{c \cdot n}\bot{{+ ( {1 - c} )} \cdot n_{z\; 2}}}}\end{matrix}  & ({VIII})\end{matrix}$where N=2, c₁=c, c₂=1−c, and c is a molar ratio having values from 0 to1.

Based on the relations (VI) and (VIII), n_(y)>n_(z) at any value of themolar portion of the compound of the first type C satisfying thefollowing condition: 0≦c<1. If n_(x1)>max (n⊥, n_(y2)) and n_(x2)<min(n⊥, n_(z2)), then type of the anisotropic optical film changes from apositive B_(A)-type (n_(x)<n_(z)<n_(y)) to a positive A_(C)-type(n_(z)<n_(y)<n_(x)), when the molar ratio c changes within the specifiedrange, whereas the lower limit of the NZ-factor of anisotropic opticalfilm produced from said composition is defined by the value of NZ-factorof anisotropic optical film formed by an individual compound of thesecond type.

C. A triple composition comprising one compound of the first type (“+Acomponent”) and two compounds of the second type (“B_(A) component” and“−A component”).

This composition may be used when the presence of a polymeric (“+Acomponent”) component is required to impart certain desirable propertiesto lyotropic liquid crystal phase or solid retardation film, howeverincreasing of NZ-factor of retardation film is not desirable. In thiscase the tolerance range of NZ-factor is from 0 to +∞.

FIG. 18 summarizes the experimental data based on compositions of P1 andC1 compounds and represents a plot of the NZ-factor of the solid opticalretardation layer vs. the molar portion of the component of the secondtype in the composition and shows achievable range of values of theNZ-factor vs. composition.

Example 20

This Example describes preparation of a solid optical retardation layerof the A_(C)-type from a solution comprising a binary composition ofpoly(2,2′-disulfo-4,4′-benzidine sulfoterephthalamide) (structure 4 inTable 2) cesium salt referenced hereafter as P2, and the compound C1described in Example 17. Said composition of organic compounds iscapable of forming a joint lyotropic liquid crystal system. The rigidrod-like macromolecules of P2 are capable of aligning together with π-πstacks (columns) of board-like supramolecules C1.

The P2/C1=65/35 mol % composition was prepared as follows: 5.32 g(0.0065 mol) of cesium salt of P2 was dissolved in 475 g of de-ionizedwater (conductivity ˜5 μSm/cm); the suspension was mixed with a magnetstirrer. After dissolving, the solution was filtered with thehydrophilic nylon filter with pore size 45 μm. Separately, 1.86 g(0.0035 mol) of C1 was dissolved in 60 g of de-ionized water; thesuspension was mixed with a magnet stirrer. While stirring, 4.4 ml of 20wt. % Cesium hydroxide (0.007 mol) was gradually added drop-by-drop intosuspension for approximately 15 minutes until a clear solution wasformed. Clear solutions of P2 and C1 were mixed together to form 547 gof a clear solution. This composition was concentrated on a rotaryevaporator in order to remove an excess of water and formed 127 g of abinary composition representing a lyotropic liquid crystal (LLC)solution. The total concentration of the composition (P2+C1) C_(TOT) wasequal to about 6 wt. %.

The coatings were produced and optically characterized as described inthe Example 14. The value of NZ-factor of the coatings is equal to about2.0.

Example 21

This Example describes the preparation of a solid optical retardationlayer of B_(A)-type from a solution comprising a binary composition ofthe organic compounds P2 described in Example 20 and C1 described inExample 17.

The P2/C1=35/65 molar % composition was prepared as follows: 2.86 g(0.0035 mol) of the cesium salt of P2 was dissolved in 70 g ofde-ionized water (conductivity ˜5 μm/cm); the suspension was mixed witha magnet stirrer. After dissolving, the solution was filtered at thehydrophilic nylon filter with pore size 45 μm. Separately, 3.44 g(0.0065 mol) of C1 was dissolved in 103 g of de-ionized water;suspension was mixed with a magnet stirrer. While stirring, 7.75 ml of20 wt. % Cesium hydroxide was gradually added drop-by-drop into thesuspension for approximately 15 minutes until a clear solution wasformed. Clear solutions of P2 and C1 were mixed together to form 400 gof a clear solution. This composition was concentrated on a rotaryevaporator in order to remove an excess of water and form 70 g of abinary composition representing a lyotropic liquid crystal (LLC)solution. The total concentration of composition (P2+C1) C_(TOT) wasequal to about 11%.

The coatings were produced and optically characterized, as was describedin Example 14, however, Gardner® wired stainless steel rod #4 was usedinstead of Gardner® wired stainless steel rod #8. The obtained solidoptical retardation layer was characterized by principle refractiveindices, which obey the following condition: n_(x)<n_(z)<n_(y). TheNZ-factor at the wavelength λ=550 nm is equal to about 0.7.

Example 22

This Example describes preparation of a solid optical retardation layerof the A_(C)-type from a solution comprising a binary composition ofpoly(2,2′-disulfo-4,4′-benzidine naphthalene-2,6-dicarboxamide)(structure 7 in Table 2) referenced hereafter as P3, and C1 described inExample 17. Said composition of organic compounds is capable of forminga joint lyotropic liquid crystal system. The rigid rod-likemacromolecules of P3 are capable of aligning together with π-π (stacks(columns) of board-like supramolecules C1.

The P3/C1=65/35 mol % composition was prepared as follows: 5.12 g(0.0065 mol) of cesium salt of P3 was dissolved in 475 g of de-ionizedwater (conductivity ˜5 μSm/cm); the suspension was mixed with a magnetstirrer. After dissolution, the solution was filtered with thehydrophilic nylon filter with pore size 45 μm. Separately, 1.86 g(0.0035 mol) of C1 was dissolved in 60 g of de-ionized water; thesuspension was mixed with a magnet stirrer. While stirring, 4.4 ml of 20wt. % Cesium hydroxide (0.007 mol) was gradually added drop-by-drop intosuspension for approximately 15 minutes until a clear solution wasformed. Clear solutions of P3 and C1 were mixed together to form 547 gof a clear solution. This composition was concentrated on a rotaryevaporator in order to remove an excess of water and form 127 g of abinary composition representing a lyotropic liquid crystal (LLC)solution. The total concentration of the composition (P3+C1) C_(TOT) wasequal to about 6 wt. %.

The coatings were produced and optically characterized as described inthe Example 14. The value of NZ-factor of the coatings is equal to about2.4.

Example 23

This Example describes the preparation of a solid optical retardationlayer of B_(A)-type from a solution comprising a binary composition ofthe same organic compounds P3 and C1 described in Example 17.

P3/C1=30/70 molar % composition was prepared as follows: 2.36 g (0.0030mol) of the cesium salt of P3 was dissolved in 70 g of de-ionized water(conductivity ˜5 μSm/cm); the suspension was mixed with a magnetstirrer. After dissolving, the solution was filtered at the hydrophilicnylon filter with pore size 45 μm. Separately, 3.70 g (0.0070 mol) of C1was dissolved in 103 g of deionized water; suspension was mixed with amagnet stirrer. While stirring, 7.75 ml of 20 wt. % Cesium hydroxide wasgradually added drop-by-drop into the suspension for approximately 15minutes until a clear solution was formed. Clear solutions of P3 and C1were mixed together to form 400 g of a clear solution. This compositionwas concentrated on a rotary evaporator in order to remove an excess ofwater and form 70 g of a binary composition representing a lyotropicliquid crystal (LLC) solution. The total concentration of composition(P3+C1) C_(TOT) was equal to about 11%.

The coatings were produced and optically characterized as described inExample 14, however, Gardner® wired stainless steel rod #4 was usedinstead of Gardner® wired stainless steel rod #8. The obtained solidoptical retardation layer is characterized by the thickness equal toapproximately 350 nm and the principle refractive indices, which obeythe following condition: n_(x)<n_(z)<n_(y). The NZ-factor at thewavelength λ=550 nm is equal to about 0.6.

The above described examples show the ability to tailor the degree ofbiaxiality of the solid optical retardation layer by varying ratio ofthe organic compounds of the first and the second type in thecomposition.

Example 24

FIG. 19 shows the cross section of an optical film formed on substrate1. The film contains solid optical retardation layer 2, adhesive layer3, and protective layer 4. The solid optical retardation layer can bemanufactured using methods described in Examples 14 or 16. The polymerlayer 4 protects the optical crystal film from damage in the course ofits transportation.

This optical film is a semiproduct, which may be used in LCDs as forexample an external retarder. Upon removal of the protective layer 4,the optical film can be applied onto a glass with adhesive layer 3.

Example 25

The above described optical film with an additional antireflection layer5 formed on the substrate can be applied to the LCD front surface (FIG.20). For example, an antireflection layer of silicon dioxide reduces by30% the fraction of light reflected from the LCD front surface.

Example 26

With the above described optical film applied to the front surface of anelectrooptical device or an LCD, an additional reflective layer 6 can beformed on the substrate (FIG. 21). The reflective layer may be obtained,for example, by depositing an aluminium film

Example 27

In this Example, the solid optical retardation layer 2 is applied ontothe diffuse or specular semitransparent reflector 6 that serves as asubstrate (FIG. 22). The reflector layer 6 may be covered with theplanarization layer 7 (optional). Polyurethane or an acrylic polymer orany other material can be used for making this planarization layer.

Example 28

This example describes a multidomain vertical alignment liquid crystaldisplay (MVA LCD) compensated with a single biaxial A_(C)-type plateaccording to the present invention. The optical layers of the simulatedMVA LCD design are shown in FIG. 23 and comprise two polarizers, 8 and11, arranged on each side of the liquid crystal cell 10, and onecompensating structure 9 located between the front polarizer 8 and theliquid crystal cell 10.

The LCD further comprises a backlight 12. The compensating structurecomprises a single retardation layer characterized by two in-planerefractive indices (nf and ns) corresponding to a fast principal axisand a slow principal axis respectively, and one refractive index (nn) inthe normal direction which obey the following conditions forelectromagnetic radiation in the visible spectral range: ns>nf>nn. Thisretardation layer is biaxial A_(C)-type plate having the followingparameters: thickness d=1.2 microns and n_(s)=1.72, n_(f)=1.68,n_(n)=1.62 (n_(s)>n_(f)>n_(n)) at wavelength λ=550 nm. The preparationof this type retardation layer is described in Examples 17, 20 and 22,wherein n_(x)=n_(s), n_(y)=n_(f), and n_(z)=n_(n).

The front 8 and rear 11 polarizers each comprise one inner TAC layerwith typical properties of negative C-type plate providing a retardationof 50 nm. This TAC film retardation influences the optical compensationand is taken into account. The setup is based on a multidomain verticalalignment liquid crystal (MVA LC) cell wherein four LC domains withreorientation planes at azimuth angles 45, 135, −45, −135 are used. Thethickness d of the VA cell was chosen on account of the LC opticalanisotropy Δn in order to provide a cell retardation of Δnd≈=275 nm. TheLC director pretilt angle with respect to the layer surface is 89°. TheLC material with negative dielectric anisotropy (ε_(∥)−ε_(⊥)=−3.5) andlow birefringence (Δn≈0.08) is aligned at azimuth angles: 45, 135; −45,−135. The elastic modules of the LC used in simulations were of typicalvalues: K₁₁=10 pN, K₂₂=5 pN and K₃₃=15 pN. For the given LC parametersthe state with transmission close to the maximal value is achieved at anapplied voltage of 8 V that agrees with the experiment.

The angular orientation of principal axes of the optically anisotropicelements shown in FIG. 23 is as follows:

-   -   transmission axes of the front and rear polarizers are at φ=90°        and φ=0° respectively,    -   the n_(s) direction is at φ=90° in case of biaxial A_(C)-type        plate retarder.

Optimization of an A_(C)-type plate thickness was performed for maximalcontrast ratio at 550 nm. The contrast ratio vs. viewing angle is shownin FIGS. 24a and 24b. For comparison the contrast ratio vs. viewingangle of the non-compensated multidomain vertical alignment liquidcrystal display (MVA LCD) is shown in FIGS. 25a and 25b.

Example 29

This Example describes the multidomain vertical alignment liquid crystaldisplay (MVA LCD) compensated with a biaxial A_(C)-type plate anduniaxial negative C-plate according to the present invention. Theoptical layers of the simulated MVA LCD design are shown in FIG. 26 andcomprise two polarizers, 8 and 11, arranged on each side of the liquidcrystal cell 10, and one compensating structure 9 located between thefront polarizer 8 and the liquid crystal cell 10. The LCD comprises abacklight 12 also. The compensating structure comprises a biaxialA_(C)-type plate 14 and uniaxial negative C-plate 13, which has anoptical axis perpendicular to the plate. The biaxial A_(C)-type platehas the following parameters: thickness d=1.2 microns and n_(s)=1.72,n_(f)=1.68, n_(n)=1.62 (n_(s)>n_(f)>n_(n)) at wavelength λ=550 nm. Thepreparation of this type retardation layer is described in Examples 17,20 and 22, wherein n_(x)=n_(s), n_(y)=n_(f), and n_(z)=n_(n). Theuniaxial negative C-plate is characterized by retardation which is equalto 70 nm.

The front 8 and rear 11 polarizers each comprise TAC layers with typicalproperties of negative C-type plate providing a retardation of 50 nm.This TAC film retardation influences the optical compensation and istaken into account. The setup is based on a multidomain verticalalignment liquid crystal (MVA LC) cell wherein four LC domains withreorientation planes at azimuth angles 45, 135, −45, −135 are used. Thethickness d of the VA cell was chosen on account of the LC opticalanisotropy Δn in order to provide a cell retardation of Δnd≈275 nm. TheLC director pretilt angle with respect to the layer surface was 89°. TheLC material with negative dielectric anisotropy (ε_(∥)−ε_(⊥)=−3.5) andlow birefringence (λn≈0.08) is aligned at azimuth angles: 45, 135; −45,−135. The elastic modules of the LC used in simulations were of typicalvalues: K₁₁=10 pN, K₂₂=5 pN and K₃₃=15 pN. The state with transmissionclose to the maximal value with such LC parameters is achieved at anapplied voltage of 8 V that agrees with the experiment.

The angular orientation of principal axes of the optically anisotropicelements shown in FIG. 26 is as follows:

-   -   transmission axes of the front and rear polarizers are at φ=90°        and φ=0° respectively,    -   the n_(s) direction is at φ=90° in case of biaxial A_(C)-type        plate retarder.

The contrast ratio vs. viewing angle of optimal double-plate compensatedMVA LCD is shown in FIGS. 27a and 27b. For comparison the contrastratios vs. viewing angle for no compensation (curve 1), single platecompensation (curve 2), and double plate compensation (curve 3) ofmultidomain vertical alignment liquid crystal display (MVA LCD) areshown in FIG. 28.

Although the present invention has been described in detail withreference to a particular preferred embodiment, persons possessingordinary skill in the art to which this invention pertains willappreciate that various modifications and enhancements may be madewithout departing from the spirit and scope of the claims that follow.

What is claimed is:
 1. A composition comprising: at least one organiccompound of a first type or its salt, and at least one organic compoundof a second type, wherein the organic compound of the first type has thegeneral structural formula I

where Core is a conjugated organic unit capable of forming a polymericrigid rod-like macromolecule, n is a number of the conjugated organicunits in the polymeric rigid rod-like macromolecule, G_(k) is a set ofionogenic side-groups, and k is a number of the side-groups in the setG_(k); wherein the ionogenic side-groups and the number k providesolubility of the organic compound of the first type in a solvent andgive rigidity to the rod-like macromolecule; the number n providesmolecule anisotropy that promotes self-assembling of macromolecules in asolution of the organic compound or its salt, wherein the number k isequal to 0, 1, 2, 3, 4, 5, 6, 7, or 8, and the number n is an integer inthe range from 10 to 10000; wherein the rod-like macromolecule has apolymeric main rigid-chain, wherein at least one rigid-core polymer is acopolymer having conjugated organic unit has the general structuralformula IV[-(Core1)-S1-(Core2)-S2-]_(n-t)[-(Core3)-S3-[(Core4)-S4-]_(j)]_(t)  (IV) wherein Core1, Core2, Core3 and Core4 are conjugated organiccomponents, spacers S1, S2, S3 and S4 are selected independently fromthe group consisting of —CO—NH—, —NH—CO—, —O—NH—, linear and branched(C₁-C₄)alkylenes, linear and branched (C₁-C₄)alkenylenes,(C₂-C₂₀)polyethylene glycols, —O—CH₂—, —CH₂—O—, —CH═CH—, —CH═CH—COO—,—OOC—CH═CH—, —CO—CH₂—, —OCO—O—, —OCO—, —C≡C—, —CO—S—, —S—, —S—CO—, —O—,—NH—, —N(CH₃)—, n is an integer in the range from 10 to 10000, t is aninteger in the range from 1 to n-1 and j is 0 or 1, and wherein theconjugated organic component Core3 differs from Core1or Core 2 Core1 orCore2, or Core4 differs from Core1 or Core2; wherein the conjugatedorganic components Core1, Core2, Core3 and Core4 comprising compriseionogenic groups side-groups G and are selected from the structuresbased on benzene ring and naphthalene and having general formula 1 toand 2:

wherein the ionogenic side-groups G are selected from the groupconsisting of —COOH, —S0 ₃H —SO₃H, and —H₂PO₃, k is equal 0, 1 or 2, pis equal to 1, 2 or 3; and wherein the organic compound of the secondtype has the general structural formula II

where Sys is an at least partially conjugated substantially planarcyclic or polycyclic molecular system; X, Y, Z, and Q are substituents;substituent X is a carboxylic group —COOH, m is 0, 1, 2, 3 or 4;substituent Y is a sulfonic group —SO₃H, h is 0, 1, 2, 3 or 4;substituent Z is a carboxamide —CONH₂, p is 0, 1, 2, 3 or 4; substituentQ is a sulfonamide —SO₂NH₂, v is 0, 1, 2, 3 or 4; wherein the organiccompound of the second type is capable of forming board-likesupramolecules via π-π-interaction, and wherein the composition iscapable of forming a lyotropic liquid crystal solution, and saidsolution is capable of forming a solid retardation layer substantiallytransparent to electromagnetic radiation in the visible spectral range;wherein Sys is selected from the structures with general formula 14 to20:


2. A composition according to claim 1, wherein the type and degree ofbiaxiality of the solid retardation layer is controlled by a molar ratioof the organic compounds of the first and the second type in thecomposition.
 3. A composition according to claim 1, wherein the rigidrod-like macromolecule has a copolymeric main rigid-chain, and whereinat least one conjugated organic unit is different from the others.
 4. Acomposition according to claim 1, wherein the organic compound of thefirst type is selected from structures 3 to 13, wherein the ionogenicside-group G is a sulfonic group —SO₃H, and k is equal to 0, 1 or 2:


5. A composition according to claim 1, wherein the organic compound ofthe first type further comprises additional side-groups independentlyselected from the group consisting of linear and branched (C₁-C₂₀)alkyl,(C₂-C₂₀)alkenyl, and (C₂-C₂₀)alkinyl (C₂-C₂₀)alkynyl.
 6. A compositionaccording to claim 5, wherein at least one of the additional side-groupsis connected with the Core via a bridging group A selected from thegroup consisting of —C(O)—, —C(O)O—, —C(O)—NH—, —(SO₂)NH—, —O—, —CH₂O—,—NH—, >N—, and any combination thereof.
 7. A composition according toclaim 1, wherein the salt of the organic compound of the first type isselected from the group consisting of ammonium and alkali-metal salts.8. A composition according to claim 1, further comprising inorganiccompounds which are selected from the group consisting of hydroxides andsalts of alkali metals.
 9. An optical film comprising: a substratehaving front and rear surfaces, and at least one solid opticalretardation layer on the front surface of the substrate, wherein thesolid optical retardation layer comprises at least one organic compoundof a first type or its salt, and at least one organic compound of asecond type, wherein the organic compound of the first type has thegeneral structural formula I

where Core is a conjugated organic unit capable of forming a polymericrigid rod-like macromolecule, n is a number of the conjugated organicunits in the polymeric rigid rod-like macromolecule, G_(k) is a set ofionogenic side-groups, and k is a number of the side-groups in the setG_(k); wherein the ionogenic side-groups and the number k providesolubility of the organic compound of the first type in a solvent andgive rigidity to the rod-like macromolecule; the number n providesmolecule anisotropy that promotes self-assembling of macromolecules in asolution of the organic compound or its salt, wherein the number k isequal to 0, 1, 2, 3, 4, 5, 6, 7, or 8, and the number n is an integer inthe range from 10 to 10000; wherein the rod-like macromolecule has apolymeric main rigid-chain, wherein at least one rigid-core polymer is acopolymer having conjugated organic unit has the general structuralformula IV[(Core1)-S1-(Core2)-S2-]_(n-t)[-(Core3)-S3-[(Core4)-S4-]_(j)]_(t)   (IV)wherein Core1, Core2, Core3 and Core4 are conjugated organic components,spacers S1, S2, S3 and S4 are selected independently from the groupconsisting of —CO—NH—, —NH—CO—, —O—NH—, linear and branched(C₁-C₄)alkylenes, linear and branched (C₁-C₄)alkenylenes,(C₂-C₂₀)polyethylene glycols, —O—CH₂—, —CH₂—O—, —CH═CH—, —CH═CH—COO—,—OOC—CH═CH—, —CO—CH₂—, —OCO—O—, —OCO—, —C≡C—, —CO—S—, —S—, —S—CO—, —O—,—NH—, —N(CH₃)—, n is an integer in the range from 10 to 10000, t is aninteger in the range from 1 to n-1 and j is 0 or 1, and wherein theconjugated organic component Core3 differs from Core1or Core 2 Core1 orCore2, or Core4 differs from Core1 or Core2; wherein the conjugatedorganic components Core1, Core2, Core3 and Core4 comprising compriseionogenic groups side-groups G and are selected from the structuresbased on benzene ring and naphthalene and having general formula 1 toand 2:

wherein the ionogenic side-groups G are selected from the groupconsisting of —COOH, —SO₃H, and —H₂PO₃, k is equal 0, 1 or 2, p is equalto 1, 2 or 3; and wherein the organic compound of the second type hasthe general structural formula II

where Sys is an at least partially conjugated substantially planarcyclic or polycyclic molecular system; X, Y, Z, and Q are substituents;substituent X is a carboxylic group —COOH, m is 0, 1, 2, 3 or 4;substituent Y is a sulfonic group —SO₃H, h is 0, 1, 2, 3 or 4;substituent Z is a carboxamide —CONH₂, p is 0, 1, 2, 3 or 4; substituentQ is a sulfonamide —SO₂NH₂, v is 0, 1, 2, 3 or 4; wherein the organiccompound of the second type is capable of forming board-likesupramolecules via π-π-interaction, and solid optical retardation layersubstantially transparent to electromagnetic radiation in the visiblespectral range; wherein Sys is selected from the structures with generalformula 14 to 20:


10. An optical film according to claim 9, wherein the type and degree ofbiaxiality of the said optical retardation layer is controlled by amolar ratio of the organic compounds of the first and the second type inthe composition.
 11. An optical film according to claim 9, wherein therod-like macromolecule has a polymeric main rigid-chain, and wherein theconjugated organic units are the same.
 12. An optical film according toclaim 9, wherein the rigid rod-like macromolecule has a copolymeric mainrigid-chain, and wherein at least one conjugated organic unit isdifferent from the others.
 13. An optical film according to claim 9,wherein the organic compound of the first type is selected fromstructures 3 to 13, wherein the ionogenic side-group G is sulfonic group—SO₃H, and k is equal to 0, 1 or 2:


14. An optical film according to claim 9, wherein the organic compoundof the first type further comprises additional side-groups independentlyselected from the group consisting of linear and branched (C₁-C₂₀)alkyl,(C₂-C₂₀) alkenyl, and (C₂-C₂₀)alkinyl (C₂-C₂₀)alkynyl.
 15. A opticalfilm according to claim 14, wherein at least one of the additionalside-groups is connected with the Core via a bridging group A selectedfrom the group consisting of —C(O)—, —C(O)O—, —C(O)—NH—, —(SO₂)NH—, —O—,—CH₂O—, —NH—, >N—, and any combination thereof.
 16. An optical filmaccording to claim 9, wherein the salt of the organic compound of thefirst type is selected from the group consisting of ammonium andalkali-metal salts.
 17. An optical film according to claim 9, furthercomprising inorganic compounds which are selected from the groupconsisting of hydroxides and salts of alkali metals.
 18. An optical filmaccording to claim 9, wherein said solid retardation layer is generallya biaxial retardation layer possessing has two refractive indices(n_(x, and ny)) (n_(x) and n_(y)) corresponding to two mutuallyperpendicular directions in the plane of the substrate front surface andone refractive index (n_(z)) in the normal direction to the substratefront surface, and wherein the refractive indices obey the followingcondition: n_(x)≠n_(z)≠n_(y).
 19. An optical film according to claim 18,wherein the refractive indices obey the following condition:n_(z)<n_(y)<n_(x).
 20. An optical film according to claim 18, whereinthe refractive indices obey the following condition: n_(x)<n_(z)<n_(y).21. An optical film according to claim 9, wherein the substratecomprises a material is selected from the group consisting of a polymerand glass.
 22. An optical film according to claim 9, wherein thesubstrate's front and rear surfaces are flat or curved or anycombination thereof.
 23. A liquid crystal display comprising a verticalalignment mode liquid crystal cell, two polarizers, arranged one on eachside of the liquid crystal cell, and at least one compensating structurelocated between said polarizers, wherein the polarizers havetransmission axes which are perpendicular to each other, and thecompensating structure comprises at least one retardation layer, whereinthe retardation layer comprises at least one organic compound of a firsttype or its salt, and at least one organic compound of a second type,wherein the organic compound of the first type has the generalstructural formula I

where Core is a conjugated organic unit capable of forming a polymericrigid rod-like macromolecule, n is a number of the conjugated organicunits in the polymeric rigid rod-like macromolecule, G_(k) is a set ofionogenic side-groups, and k is a number of the side-groups in the setG_(k); wherein the ionogenic side-groups and the number k providesolubility of the organic compound of the first type in a solvent andgive rigidity to the rod-like macromolecule; the number n providesmolecule anisotropy that promotes self-assembling of macromolecules in asolution of the organic compound or its salt, wherein the number k isequal to 0, 1, 2, 3, 4, 5, 6, 7, or 8, and the number n is an integer inthe range from 10 to 10000; wherein the rod-like macromolecule has apolymeric main rigid-chain, wherein at least one rigid-core polymer is acopolymer having conjugated organic unit has the general structuralformula IV[-(Core1)-S1-(Core2)-S2-]_(n-t)[-(Core3)-S3-[(Core4)-S4-]_(j)]_(t)  (IV) wherein Core1, Core2, Core3 and Core4 are conjugated organiccomponents, spacers S1, S2, S3 and S4 are selected independently fromthe group consisting of —CO—NH—, —NH—CO—, —O—NH—, linear and branched(C₁-C₄)alkylenes, linear and branched (C₁-C₄)alkenylenes,(C₂-C₂₀)polyethylene glycols, —O—CH₂—, —CH₂—O—, —CH═CH—, —CH═CH—COO—,—OOC—CH═CH—, —CO—CH₂—, —OCO—O—, —OCO—, —C≡C—, —CO—S—, —S—, —S—CO—, —O—,—NH—, N(CH₃)—, n is an integer in the range from 10 to 10000, t is aninteger in the range from 1 to n-1 and j is 0 or 1, and wherein theconjugated organic component Core3 differs from Core1 or Core 2 Core2,or Core4 differs from Core1 or Core2; wherein the conjugated organiccomponents Core1, Core2, Core3 and Core4 comprising comprise ionogenicgroups side-groups G and are selected from the structures based onbenzene ring and naphthalene and having general formula 1 to and 2:

wherein the ionogenic side-groups G are selected from the groupconsisting of —COOH, —SO₃H, and —H₂PO₃, k is equal 0, 1 or 2, p is equalto 1, 2 or 3; and wherein the organic compound of the second type hasthe general structural formula II

where Sys is an at least partially conjugated substantially planarcyclic or polycyclic molecular system; X, Y, Z, and Q are substituents;substituent X is a carboxylic group —COOH, m is 0, 1, 2, 3 or 4;substituent Y is a sulfonic group —SO₃H, h is 0, 1, 2, 3 or 4;substituent Z is a carboxamide —CONH₂, p is 0, 1, 2, 3 or 4; substituentQ is a sulfonamide —SO₂NH₂, v is 0, 1, 2, 3 or 4; wherein the organiccompound of the second type is capable of forming board-likesupramolecules via π-π-interaction, and wherein the composition iscapable of forming a lyotropic liquid crystal solution, and saidsolution is capable of forming a solid biaxial retardation layersubstantially transparent to electromagnetic radiation in the visiblespectral range; wherein Sys is selected from the structures with generalformula 14 to 20:


24. A liquid crystal display according to claim 23, wherein the rod-likemacromolecule has a polymeric main rigid-chain, and wherein theconjugated organic units are the same.
 25. A liquid crystal displayaccording to claim 23, wherein the rigid rod-like macromolecule has acopolymeric main rigid-chain, and wherein at least one conjugatedorganic unit is different from the others.
 26. A liquid crystal displayaccording to claim 23, wherein the organic compound of the first type isselected from structures 3 to 13, wherein the ionogenic side-group G asulfonic group —SO₃H, and k is equal to 0, 1 or 2:


27. A liquid crystal display according to claim 23, wherein the organiccompound of the first type further comprises additional side-groupsindependently selected from the group consisting of linear and branched(C₁-C₂₀)alkyl, (C₂-C₂₀) alkenyl, and (C₂-C₂₀)alkinyl (C₂-C₂₀)alkynyl.28. A liquid crystal display according to claim 27, wherein at least oneof the additional side-groups is connected with the Core via a bridginggroup A selected from the group consisting of —C(O)—, —C(O)O—,—C(O)—NH—, —(SO₂)NH—, —O—, —CH₂O—, —NH—, >N—, and any combinationthereof.
 29. A liquid crystal display according to claim 23, wherein thesalt of the organic compound of the first type is selected from thegroup consisting of ammonium and alkali-metal salts.
 30. A liquidcrystal display according to claim 23, further comprising inorganiccompounds which are selected from the group consisting of hydroxides andsalts of alkali metals.
 31. A liquid crystal display according to claim23, wherein the compensating structure comprises the single retardationlayer which is characterized by two in-plane refractive indices (nf andns) corresponding to a fast principal axis and a slow principal axisrespectively, and one refractive index (nn) in the normal directionwhich obey the following conditions for electromagnetic radiation in thevisible spectral range: ns>nf>nn.
 32. A liquid crystal display accordingto claim 23, wherein at least one compensating structure is locatedbetween the liquid crystal cell and one of said polarizers.
 33. A liquidcrystal display according to claim 23, wherein at least one compensatingstructure is located inside the liquid crystal cell.
 34. A liquidcrystal display according to claim 23, comprising at least twocompensating structures located on each side of the liquid crystal cell.35. A liquid crystal display according to claim 31, further comprisingan additional retardation layer which is characterized by two in-planerefractive indices (nf and ns) corresponding to a fast principal axisand a slow principal axis respectively, and one refractive index (nn) inthe normal direction which obey the following conditions forelectromagnetic radiation in the visible spectral range: ns=nf>nn.
 36. Aliquid crystal display according to claim 23, wherein at least one ofthe two polarizers comprises at least one retardation TAC-layer whereTAC is triacetyl cellulose.
 37. A composition comprising: (a) an organiccompound of a first type or its salt, comprising structural formula I

 wherein Core is a conjugated organic unit, and n is a number ofconjugated organic units from 10 to 10000; G_(k) is a set of ionogenicside-groups, and k is a number of side-groups in the set from 0 to 8;Core has structural formula III-(Core1)-S1-(Core2)-S2-   (III) wherein Core1 and Core2 are conjugatedorganic components selected from structures of formula (1) and (2):

G are ionogenic side-groups selected from the group consisting of —COOH,—SO₃H, and —H₂PO₃; k is equal 0, 1 or 2; and p is equal to 1, 2 or 3; S1and S2 are spacers selected independently from the group consisting of—CO—NH—, —NH—CO—, —O—NH—, linear and branched (C₁-C₄)alkylenes, linearand branched (C₁-C₄)alkenylenes, (C₂-C₂₀)polyethylene glycols, —O—CH₂—,—CH₂—O—, —CH═CH—, —CH═CH—COO—, —OOC—CH═CH—, —CO—CH₂—, —OCO—O—, —OCO—,—C≡C—, —CO—S—, —S—, —S—CO—, —O—, —NH—, and —N(CH₃)— and (b) an organiccompound of a second type having structural formula II

 wherein X, Y, Z, and Q are substituents, wherein X is —COOH, m is 0, 1,2, 3 or 4; Y is —SO₃H, h is 0, 1, 2, 3 or 4; Z is —CONH₂, p is 0, 1, 2,3 or 4; Q is —SO₂NH₂, v is 0, 1, 2, 3 or 4; and Sys is selected fromstructures of formula 14 to 20:


38. The composition of claim 37, wherein the organic compound of thefirst type has a structure selected from any one of structures 3 to 13or a salt of any one of structures 3 to 13:


39. The composition of claim 37, wherein the organic compound of thefirst type has structure 3 or a salt of structure 3:


40. The composition of claim 37, wherein the organic compound of thesecond type has structure 28:


41. The composition of claim 37, wherein the organic compound of thefirst type has structure 3

and the compound of the second type has structure 28


42. An optical film comprising a substrate having front and rearsurfaces and at least one solid optical retardation layer on the frontsurface of the substrate, wherein the solid optical retardation layercomprises a composition of claim
 37. 43. An optical film comprising asubstrate having front and rear surfaces and at least one solid opticalretardation layer on the front surface of the substrate, wherein thesolid optical retardation layer comprises a composition of claim
 38. 44.An optical film comprising a substrate having front and rear surfacesand at least one solid optical retardation layer on the front surface ofthe substrate, wherein the solid optical retardation layer comprises acomposition of claim
 39. 45. An optical film comprising a substratehaving front and rear surfaces and at least one solid opticalretardation layer on the front surface of the substrate, wherein thesolid optical retardation layer comprises a composition of claim
 40. 46.An optical film comprising a substrate having front and rear surfacesand at least one solid optical retardation layer on the front surface ofthe substrate, wherein the solid optical retardation layer comprises acomposition of claim
 41. 47. A liquid crystal display comprising avertical alignment mode liquid crystal cell, a polarizer on each side ofthe liquid crystal cell, and at least one compensating structure locatedbetween said polarizers, wherein the polarizers have transmission axeswhich are perpendicular to each other, and the compensating structurecomprises at least one retardation layer, wherein the retardation layercomprises a composition of claim
 37. 48. A liquid crystal displaycomprising a vertical alignment mode liquid crystal cell, a polarizer oneach side of the liquid crystal cell, and at least one compensatingstructure located between said polarizers, wherein the polarizers havetransmission axes which are perpendicular to each other, and thecompensating structure comprises at least one retardation layer, whereinthe retardation layer comprises a composition of claim
 38. 49. A liquidcrystal display comprising a vertical alignment mode liquid crystalcell, a polarizer on each side of the liquid crystal cell, and at leastone compensating structure located between said polarizers, wherein thepolarizers have transmission axes which are perpendicular to each other,and the compensating structure comprises at least one retardation layer,wherein the retardation layer comprises a composition of claim
 39. 50. Aliquid crystal display comprising a vertical alignment mode liquidcrystal cell, a polarizer on each side of the liquid crystal cell, andat least one compensating structure located between said polarizers,wherein the polarizers have transmission axes which are perpendicular toeach other, and the compensating structure comprises at least oneretardation layer, wherein the retardation layer comprises a compositionof claim
 40. 51. A liquid crystal display comprising a verticalalignment mode liquid crystal cell, a polarizer on each side of theliquid crystal cell, and at least one compensating structure locatedbetween said polarizers, wherein the polarizers have transmission axeswhich are perpendicular to each other, and the compensating structurecomprises at least one retardation layer, wherein the retardation layercomprises a composition of claim 41.